The Value Of Expression In Portraiture.

           A matter to which many portrait photographers do not give the consideration that it merits, is the expression of the sitter's countenance at the moment of the exposure. In my experience and observation the one thing more, perhaps, than any other single quality, which secures approval or disapproval of a portrait, is the sitter's expression. I was speaking in this sense recently to an old photographer, now a director of a firm having several studios of good class, and he replied that he would undertake to build up a business by attention to the matter of the sitter's expression, when on technique he could not do so. It is not to be supposed that the speaker thinks slightingly of the importance of good sound photography. He recognizes, as I do, that that should be the foundation on which our work should be based, but that for securing the satisfaction of our patrons he considered the presentation of a pleasing expression to be the most important factor.
           To some extent the desirability of securing an agreeable expression in a portrait has been recognized from the early days of professional photography. A stock wheeze of the "comic" papers has been to represent the photographer as telling the sitter to "look pleasant." There may be photographers who use this formula; I don't remember that I ever did so. A sitter, unless in the case of a skilful actor, does not look pleasant to order. I have often known a fond mother say to her baby or young child when ready for the sitting, or even before that, "Now laugh, laugh." I have never known this to succeed. The child is too young either to understand the injunction, or to be able to take the part of an actor and assume an expression not actually in accordance with its feelings. Some playful antic on the part of the photographer is much more likely to produce the desired effect. I have often found a little game of Peep-bo to succeed in attracting baby's attention and in securing an interested expression. With sitters other than infants, conversation will naturally be the means employed. With boys a little discussion as to the relative appreciation of trigonometry and football or cricket will often induce an amused expression, but here some tact is desirable. An opening sentence or two will generally show the direction into which to guide the conversation. The leading principle is not to tell the sitter to assume any particular expression, but to say or do something likely to evoke it.
           With adult sitters, tact and the avoidance of anything like taking a liberty are of the highest importance. I have known a photographer, thinking to chase away a mournful expression, tell a lady not to look as if she were in a consumption, only to be crushed by the reply, "Perhaps I am."
           A photographer ready to turn to advantage any little incident that may occur may often succeed in obtaining a happy expression that will secure a good order from the negative. One such case that occurs to me is that of a young lady of German parentage, born or long domiciled here (this occurred long before the war). The young lady had good features, but when posed for the photograph assumed a stern, almost forbidding, expression which ordinary conversation failed to remove. Presently, however, her mother said something to her in German, on which I joined in with "Ach! Wenn ich nur Deutsch verstehen konnte!" (Oh! if only I could understand German!), which, being spoken in the language of which ignorance was assumed, so tickled the lady that she burst out laughing. When the ripples of laughter had subsided but an amused expression still hung about the features, a very successful portrait was secured. With French sitters, of whom there hare been a good many this year, I have found that a little conversation in their own language generally induces an interested expression even if they speak English well, and particularly if they do not do so.
           Since commencing to write this article I happened to be in the studio of a photographer who does a high-class business at good prices - he refuses altogether to take negatives for postcards when a lady came in bringing with her a friend for a sitting. The lady complimented the photographer on her own portrait, which she said was the only one that she had with a satisfactory expression, and that she was really rather ashamed of having given away such a large number of her own portraits. Depend upon it, there is more in the value of the expression in portraiture than most photographers realise.

W. E. DEBENHAM.

Practicus In The Studio: The Camera and Lens.

           The selection of the studio camera and lens, or rather lenses, for it is a serious handicap to have to work with one only, deserves the most careful consideration, and in comparison with other items a liberal allotment should be made when planning your outlay. A badly made camera or an inferior lens will soon cause the loss of more money than is saved on their cost, and will do much to brand the work turned out as second class or worse. The operator should never work with the feeling that he could do better if he had better apparatus. Now I do rot want to convey the idea that such apparatus should necessarily be costly, and as an instance of this I may say that I recently selected for a young friend a 12x10 outfit, comprising camera, studio stand, a 12 in. f/4 portrait lens, and a 5 D. Dallmeyer f/6, at a total cost of less than 25, all being purchased from well-known London dealers.
           Broadly speaking, there are two models of studio camera: the British pattern, as made by Hare, Watson, and several other makers, and the German model, which has been extensively copied by English makers. For practical purposes there is little to choose between them. When choosing a camera it is desirable to have one which is not permanently built into its stand, as in the case of any accident to the latter the whole outfit is rendered useless; besides this, it is impossible to get the camera near the floor, which is often necessary when taking children's portraits.
           Movements’ essential to the studio camera are rack and pinion or screw focusing. Personally I prefer the latter, although it is considered rather out of date now, as it never gives trouble by becoming loose and allowing the back to move, besides being conveniently placed in a fixed position. There should be vertical and side wings to the back and a rising front; the bellows should be of ample length, bearing in mind that lenses of much greater focal length are now used than was formerly the case. Twenty-four inches is not an uncommon length, so that for a 4*(1/2)-in. head on a 12 x 10 plate we require an extension of 36 ins. This should not be lost sight of if one is offered an otherwise suitable camera of old pattern, although the defect may be remedied by fitting a cone extension or "box front." Whatever camera is selected it should be well cared for and not allowed to become covered with the black greasy patches one too often sees. In passing I may remark that ordinary spirits of turpentine is an excellent medium for cleaning dirty woodwork, and an hour's work with it, followed by some good furniture cream, will often make a camera and stand look worth 50 per cent, more than when you started.
           It is very usual to fix repeating backs so that two half- or quarter-plates can be used side by side. This is a survival of wet plate days, when it was no more trouble to coat and sensitize a whole-plate than one-half or quarter the size. I think that the American plan of "one slide, one exposure" much more handy and safe. Many of the American studio stands have racks on either side, one for unexposed and the other for exposed, a dozen or more cheap single slides each for a 7 x 5 (American half-plate) being supplied with the camera. Double exposures can then only be made by the grossest carelessness. Another "Yankee notion" which is a good one is to make the pushing of the slide into the exposing position open the shutter. This has been improved upon by Messrs. Dallmeyer, who introduced a back in which double flap exposing shutter slipped along with the slide, so that the lens did not require covering before the slide was opened; this saves much time. In my opinion, any camera-maker who would supply such a device fitted with a number of cheap slides would find his reward. Think of the convenience of being able to make a couple of dozen exposures without having to refill.
           If the ordinary stands do not seem satisfactory to you, the platform style, of which the Hana and the Semi-Centennial are the best known examples, will probably meet all requirements. In these a Platform carrying the camera travels between two uprights, and the camera may be placed as high as an ordinary person can see to focus at or lowered to a few inches from the floor, the castors should be rubber-shod, and, if possible, a brake fitted, so that there is no risk of moving the camera when inserting the slide. The lens shutter is an important feature in studio apparatus, and the rubber fittings thereof have probably conduced to more profanity than all the rest of the outfit. I like the feel of a ball and tube while it is in good condition, but that is usually only for a brief period before it begins playing tricks before an important sitter. The Bowden wire cable or "Antinous" release is much move reliable, and would be better if the bicycle cable were used instead of the weaker form- usually fitted. The pressure button, too, is particularly annoying, as one cannot grab it anyhow as one can the rubber bulb, but must get hold of it just right between the fingers. It would .be quite easy to make a pear-shaped handle to work like the rubber one, and if the makers want a sketch for it I will send them one, but that will probably not be till the patent has expired.
           Now for the shutter itself, after having relieved my feelings about releases. The best shutter I have ever used, and I think I have worked with nearly every pattern, is an American one, the Packard Ideal There are several shutters, none British, of this pattern, which are probably nearly if not quite as good. It is made on the sector principle, with vulcanite leaves, and the working parts are balanced, so that very little pressure is required to actuate it. Let me confess it works best with a rubber ball and tube, the only disadvantage of which is that the rubber is too hard and the ball splits; still, if you substitute a good English bulb this trouble vanishes. The next best shutter is the velvet flap, originally introduced by Mr. James Cadett and still in use in the majority of studios under the name of the Guerry shutter. Why an English shutter had to be made in France and sold under a French name I cannot say, but so it is. The hemispherical bellows, or Grundner's shutter, is fairly satisfactory, but the interior bellows is troublesome. With the Antinous release it is much better, although the leather bellows which forms the shutter is easily injured by a. careless operator; still, on the whole, it is a good shutter.
           No less important than the camera is the lens; in fact, although with a faulty camera and a good lens we may produce excellent results, it is impossible to reverse the conditions and do so with a faulty lens upon the finest camera. The requirements of different studios vary so greatly that it is difficult to suggest the most suitable all-round selection. The length of the studio is an important factor, and I feel that I cannot do 'better than to refer the reader to the table dealing with the subject in the B.J. Almanac. Next in importance is the type of lens. Of late years there has been a growing tendency to oust the time-honoured Petzval or Dallmeyer types in favour of the rapid anastigmats. There are two sides to the question, and these have been little discussed. The anastigmat is unquestionably far superior to the portrait lens, when tried to its fullest extent, but it loses this position when only a small portion of its field is being utilized, as its cost is much greater and its qualities are wasted. If I were selecting lenses for a short studio, say, an eight-inch for cabinets and a twelve-inch for whole-plate standing figures, my choice would be an f/4.5 anastigmat of the desired focus, but if I could use a fourteen or sixteen-inch lens for cabinets I think that I should go for a portrait lens, which I could get at much less cost and which would possibly be fitted with a "diffusion of focus" adjustment. One point which I would specially impress upon the purchaser is to choose as long focus a lens as his studio will accommodate for the greater part of the work to be done. If the studio be very short, so that a 6*(1/2) or 7-inch lens has to be used for full-length cabinets, it is better to obtain at least a ten-inch lens for heads and half-lengths and to get a smaller lens for the full lengths. There are now some very cheap Anastigmats which work well, with apertures of f/6 to f/7.7, to be purchased at prices which were formerly charged for common foreign rectilinears, and these will answer for short-focus portrait work.
           There is a growing demand for soft definition in portraiture. By this I do not mean absolute fuzziness such as some selecting committees used to revel in, but a general softening of outline and suppression of small detail without loss of texture. To secure this many lenses have been introduced, and I have made negatives with most of them. The majority give too great an amount of diffusion at full aperture, and when stopped clown to reduce this exposures are unduly prolonged. For the everyday professional who wishes to make an essay in this direction I would suggest the use of the "patent" portrait lens of Dallmeyer, the recent portrait lenses of Ross, and the Cooke portrait lens. All these have adjustments which allow of any degree of diffusion up to a certain point being introduced at will, while in the case of the Ross and Dallmeyer lens a further stage may be attained by removing the back combination and using the front lens per se and in situ. There are many nameless portrait lenses, very bad as a whole, which would make excellent soft focus lenses if the back combination were taken out and lost. It should be remembered that the front lens of a portrait lens usually requires only slightly more than double the exposure of the complete lens, and not four times, as is the case with a rectilinear. The focusing eye-piece or magnifier is a very useful little adjunct to the camera outfit, as it saves eye strain and makes for certainty in focusing, especially in copying. One of fairly good quality of the Ramsden pattern will be found most satisfactory, as the field is flat and the definition good. The cheap forms with single lenses have too much spherical and chromatic aberration to be used by anyone not skilled in optical observation, and those who are would not give them house room.

PRACTICUS.

Buying Equipment

           STARTING a photographic business resembles in many respects setting up housekeeping; that is to say, there is a natural tendency to spend an undue proportion of the sum allotted for the purpose on certain big items and to stint on less showy but more essential details in other words to purchase suite- and decorations for the reception and perhaps the bedrooms, and to neglect the kitchen and scullery. In the photographer's case this has its equivalent in buying a large and elaborate camera outfit, a quantity of furniture and backgrounds, and making shift with inferior appliances in the dark and printing-rooms.
           An experienced chemist once said that when equipping a laboratory it could be assumed that after finding the cost of the principal pieces of apparatus, which the inexperienced imagined represented the bulk of the outlay, an equal amount should be allowed for sundries, which need not be purchased all at once but as required. We recently found confirmation of this judgment in the remark which a beginner in portraiture made in reply to a question as to how the business was progressing. It was to the effect that the takings were quite satisfactory, but that he had not received much benefit, as there was always something else to buy.
           If a little more judgment had been exercised in the first outlay there would have been a surplus available, and the profits of the first few months would not have been swallowed up as quickly as they were made. In our friend’s case success came quickly, and he could live and still get what was needed; bat very often it takes some months before running expenses are covered and anything that can be called a profit made.
           There is always a temptation to go in for a big studio camera. A twelve by ten with lenses to suit is usually the minimum, but the old hand knows that this size is now rarely required for direct portrait work in most studios, an, therefore, economise by getting a good whole-plate outfit and keep something in hand for the outdoor apparatus, which should be of the larger site. Any panel portraits or studio groups can be quite well taken with a good field camera and lens and in other cases large prints ran easily be made by enlarging. We are apt to forget that developing papers are now almost exclusively used, and that if only a moderate size is required there is no need to mention the fact that the prints are not made by contact. This brings us to the question of enlarging apparatus. Wherever it is possible this should be installed from the first, as it will soon save its cost, and it is preferable to select the lantern form instead of a daylight apparatus however, the latter is better than nothing. and even a fixed focus box giving an enlargement of two diameters will be found of treat value, as it enables a cabinet negative to be enlarged to twelve by ten almost as easily as the making of a contact print. As an example of the value and practicability of enlarging we may mention an order for a number of full-sized reproductions of pen-and-ink designs. These were photographed upon half-plates, and enlarged to fifteen by twelve. The difference in the price of the small and large plates made a very substantial increase in the profit on the job, and the customer was not a penny the worse.
           Great economy can be effected by properly equipping the dark-room, especially now that so much bromide work is done. Plenty of sink accommodation should be provided, and if lead be found too costly asphalt sheeting can be used as lining. It should be remembered that bench room can always be obtained by covering a sink with boards, but it is impossible to reverse the process. An efficient lamp with red and yellow filters is needed, and it is a good plan to provide a second one for the general illumination of the room; this will prevent many break-ages. A good printing box taking negatives up to whole-plate is almost a necessity nowadays even in the smallest business, for the little man who has to do every stroke himself must not have to waste time with printing frames. An ample number of dishes for developing, fixing, and washing should be provided, the larger ones being of wood lined with some waterproof material, and the smaller ones of porcelain. Vulcanite and celluloid are best avoided for professional work.
           We may now return to the studio, and consider the question of backgrounds. Where it is possible one end wall should be finished so as to serve as an interior; in addition, we require a very dark and a white ground with continuous floor cloth. When funds permit a piece of bold-patterned tapestry may be added, but scenic backgrounds are not needed except for the cheapest class of work. Chairs and tables should be, as a rule, light and dainty, such as people use every day, and not specially designed for photographic use. A heavy oak chair is a useful accessory when it is necessary to take the mayor or other celebrity.
           In the work-room especial care should be taken to facilitate output. It never should be necessary to clear the apparatus necessary for one operation before another can be started. There should be places for attaching tissue, trimming, and mounting, and these spaces should never be encroached upon.
           Retouching desks should be ample in size and firmly made. Anyone with the least .mechanical ability can make a good desk in an hour or two, always bearing in mind that the desk is made for the use of a human being and not for a negative. It is absurd to talk about quarter-plate and half-plate desks when they are supposed to accommodate a well-grown man or woman.
           It is necessary to decide what to buy before entering the dealer's portals, or it is likely that a lot of unnecessary stuff will be obtained. The purchaser should know better than the salesman what he requires. and it is only natural for the latter to try and shift such goods as are rather slow in selling. We shall not harm the dealer by this advice; his bill will come to the same, but if the tyro makes his own choice he should get what he really needs.

Assistants' notes: Celluloid Facing; Photography with the Royal Engineers; Ply Wood

Celluloid Facing.

           PHOTOGRAPHIC miniatures, which are so popular with the working-classes, are easily made; the important factor is the time taken up. By means of the card repeating back four pictures are made on a quarter-plate. Sometimes the original requires the background painted out with Chinese white, or a few touches put in with lamp black water-colour to make a bold effect. Of course, these touches are sponged off after making the negative, which should be on the contrasty side. Four (pictures are made on one piece, of glossy paper to give sharp detail, and then coloured by dyes. Celluloid facing gives an enameled appearance, and by its attractiveness helps the ale. For cementing without hot rollers use 4 parts methylated spirit, 1 part amyl acetate. Do not increase the amyl acetate unless the celluloid is thick. This is best for gelatine papers, such as glossy P.O.P. and bromide. Do not use this with collodion papers, as it dissolves the image. Cut a piece of celluloid a little larger than the print, put a few drops of above in the middle of same, then press from the centre all round outwards, in contact with blotting-paper. By making the facing little larger than the print the excite cement reach the blotting-paper and does not get on the face of picture spoiling the high gloss. With a little practice the right number of drops will be found, and no air bells formed. Major's cement, which is gelatine dissolved in glacial acetic acid, is more suitable for collodion papers, is slow in working, and if you use this cement for glossy P.O.P. and the picture should slip in the pressing down, you will find the acid has softened the image and the movement blurred the picture. Collodion papers are not suitable for dye work. - BURLINGTON.

Photography with the Royal Engineers.

           ACCOUNTS of the part that photography has played in the war have so far been written principally in terms of aircraft observation While no doubt this branch has employed more men and material than any other, and has been both organized and advertised in the energetic and efficient way characteristic of the Air Force, there has been a vast deal of photography done in connection with other departments that should not be lost sight of in considering photographic war-history. The work of official photographers of a kind hat used to be done by war correspondents is, of course, also well known as is the development in radiography; but the photography can-led out by men of the Royal Engineers has been not only extensive and varied in character, but it has not met with the recognition that its importance and quality deserves.
           ACCOUNTS Of work that takes the operator well up into the danger zone is the making of panoramic views of enemy trenches and territory. Then there is "sound-ranging." This is a marvelously ingenious and scientific method of locating enemy guns very exactly. The apparatus was invented by a Frenchman and improved by us, and as the Germans have never succeeded in capturing an instrument nor in remotely approaching the idea in efficiency, this has been a great factor in our success. The part of the photographer in this branch calls for decreasing knowledge and skill as the instrument is improved, but it calls for mention in a record. This is only one of the many rapidly growing activities of a Field Survey Battalion. These unit's are more generally known in the Army under the concise and expressive name of "Maps."
           Enormous quantities of maps are plotted, drawn, and printed "in the field," and the photographer has his share in reproducing them to various scales, both on wet and dry plates, including, of course, panchromatics. Many of the workers are old “Ordnance Survey” men, but they are not now by any means in the majority. Besides the operators there are men who print the line negatives on to zinc plates for the lithographic printers, and those who print in special variable details by true-to-scale processes. Then there are the highly skilled "glass engravers," as they style themselves, or "negative-scratchers," as would-be humorists call them. Their work, delicate and tedious, done principally with a finely sharpened needle and a magnifying glass, is at its best compared with ordinary commercial retouching as the latter is to scene-painting.
           In a published account of the success of the Intelligence Corps were mentioned, in passing, the expert photographers as assisting in its work. These also are men of the Royal Engineers. The field of photography even here is varied enough to try the skill of the best. Copying and printing in large numbers portraits of suspected persons is only one small item. These often have the unmistakable appearance of being already copies of the third or fourth generation - if I may use that expression and badly done at that; so that to make good printing negatives to give useful results is not always easy. Copying documents and posters to be used in convicting enemy officers of illegal executions is work that one could take pleasure in, notwithstanding the weird colours and crumpled conditions of some of them. Photographing parts of captured mechanism for various departments is frequently required, and even work of very technical and experimental character is successfully coped with, although it will be recognized that material, when it arrives at the place of use, often has already had a long history of careless handling and bad storage behind it, and, therefore, cannot always be considered as of all category. - D. CHARLES.

Ply Wood.

           THREE-PLY wood is now available for photographic purposes, the various restrictions having been - withdrawn, and is a useful material for either carbon transfer or for mounting enlargements. Card-board mounts require a further hacking of wood when framed, whereas a picture mounted on ply wood would go straight into the frame, having a nice appearance at the back; so if we take this advantage into account the price will compare favorably with card-board. Ply wood is made in various woods, up to seven-ply for special use, but for mounting purposes three-ply birch, which can be had "free from knots one side," 'will answer studio requirements. The albumen in the wood, by steam treatment, is made somewhat insoluble; though some call it "waterproof three-ply,” it certainly is less absorbent than the ordinary sort, and less liable to wood-worm. It does not split like ordinary panels, is superior to canvas, as holes cannot be knocked through it, can be got any size and cut any size, stretchers are dispensed with, and is the material the old masters would have welcomed with open arms. - BURLINGTON

EX CATHEDRA: Phase and Change; Strong v. Saturated Solutions; Commercial Flower Photography; Field Camera Bellows.

Phase and Change.

           While much is being talked of reconstruction on the grand scale, in the comparatively small field of photography we see things changing as the inevitable result of the circumstances of the time. The balance between the supply of and demand for labour - if that can be called a balance which a few months ago showed the latter to be immensely in excess of the former has been disturbed, and signs are plainly discernible of a reversion to the pre-war conditions under which the supply, or, at any rate, the publicly offered supply, was greater than the demand. It is easy to understand that the progress of demobilization in conjunction with the new labour which has been recruited daring the war should tend towards this condition in the ranks of photographic assistants. And the same thing is observable in respect to the firms or individuals who cater for photographers trade work. Such who have come into existence during the war now find themselves in competition with the demobilized ones who formerly had their established circle of customers, and are now taking active steps to recover their business. The circumstance provides a caution to those who may be thinking of purchasing a war-created business of this kind. A connection is difficultly held, and from several motives customers will be likely to return to those who previously had their patronage. The difficulties of supply, and, in many cases, the lower quality of work during the war period are factors which will operate in the direction of restoring custom to those who previously had it, and for this reason a business which is no more than two or three years old becomes a somewhat speculative proposition.

Strong v. Saturated Solutions.

           The keeping of certain chemicals saturated solutions is a recommendation which comes from the old days of photography when workers had a nodding acquaintance with practical chemical operations. At the present time, when such knowledge is the possession of a very small minority, the practice may lead to a degree of error which may not be suspected by the individual worker. Few will take the trouble to test the temperature of a saturated solution or to make certain that it is saturated at that temperature. And even if that is done, an awkward calculation is necessary in order to discover the quantity of solid chemical which a given volume of the solution represents. On these accounts it is a much better plan, we think, to sacrifice a measure of the concentration afforded by a saturated solution and to obtain in exchange the certainty of constant strength and the convenience of translating from solution to solid. To put this idea into a concrete shape, a saturated solution of hypo is one which varies greatly in strength according to the temperature, and at any given temperature represents per unit volume an odd weight of the chemical. A much more satisfactory and convenient plan of keeping hypo in concentrated solution is to dissolve the crystals in water and make up to a volume corresponding with twice the weight for example, 1 lb. of hypo dissolved in water to form a total bulk of 32 ozs. One ounce of hypo is then contained in every two ounces of the solution and the making up of fixing baths of any required strength becomes the simplest of arithmetical calculations. The same plan may be adopted for less soluble substances, choosing a ratio of 1:3 or 1:4 in place of the 1:2 which is possible only for such extremely soluble substances as hypo, potassium carbonate, and a few others.

Commercial Flower Photography.

           One of the most difficult branches of commercial photography is the portrayal of flowers, fruit, or vegetables for catalogue illustration, yet it is work that is frequently in demand. A good knowledge of florists, flowers and horticulture generally will go far to helping the operator in emphasizing just those points that the grower or advertiser wishes to put forward to his public. Perhaps our meaning may be the more plain if we give a simple illustration, taking the case of that popular flower the sweet pea, one, which it may be added is constantly being improved by various growers who are rapidly coming to see that one of the most direct, simple and effective methods of advertising the value of their new varieties and bringing their good points before flower-loving connoisseurs is a good photograph of a perfect bloom. Among the points looked for in the perfect sweet pea are the number of flowers that can be grown upon a single stem, their spacing upon the stalk, the length of the latter, a most important point, the size of the individual blossoms, and in connection with this an absence of what is technically termed "coarseness," and lastly the colour of the flowers. If a photograph of a perfect bloom selected at some trouble by a fastidious grower is to be a success then it will have to be something more than an ordinary hit or miss photograph of the bloom, and it will need to be arranged so that the points of the flower are shown to their best advantage. Thus the adjustment of the bloom in its holder or vase is important, likewise the position from which the picture is taken, and the rendering of its texture. In the case of vases of flowers, much the same rules will have to be followed as in the case of single specimens: nothing in the way of a "bunchy" arrangement is to be permitted. Backgrounds are best made of large sheets of mounting card of various colours, and these may also be employed for growing plants out of doors in isolating the subject from its background. Upon the technical side little need be said. An ordinary field outfit having long extension and a good lens of fairly long focus is as good an equipment as can be desired, since, except in the case of flowers growing outside, speed is not of importance. Of course, panchromatic plates and a set of screens are to be regarded as absolutely essential in order to secure correct colour rendering. A thin negative having abundant detail is best, those obtained by the tank method being highly satisfactory. It is becoming realised that a photograph is more satisfactory than one of the best drawings; colour photography is likely to popularise this branch still further, and commercial photographers should take full advantage of the demand.

Field Camera Bellows.

           The modern field camera is locked upon, and justifiably so, as an instrument of precision, and in many ways it is difficult to see how the standard design can be improved. There is one point, however, that is frequently overlooked by designers and that is the importance of fitting their instruments with bellows of sufficient width. Not only do wide bellows avoid trouble due to reflected light from their inner folds, but also it is next to impossible when using wide angle lenses of short focus to avoid some "cut off" of the image on the plate by the edges of the bellows, particularly when these are made to give a long extension. This form of trouble is the more likely to be met with in the conical bellows form than when the instrument has parallel bellows. For the latter type we must confess we have a preference, but even when conical bellows are in use there is no reason why the maker should not fit them of sufficient size to prevent the trouble referred to. Some cameras that we have seen leave much to be desired in the size of their bellows, and we can call to mind one of our own instruments that could never be used with success for wide angle work for this reason. Such a fault in an otherwise excellent design is spoiling the ship for ha'porth o' tar. When the bellows are made for long extension there is often a tendency for them to “cut off” part of the image when used at a shorter extension, and for this a loop of elastic is sometimes fitted to the top of the bellows in order to draw away the extra folds from the line of rays thrown by the lens. We have found in practice that this plan is not very satisfactory, and have supplemented the loop with two more, one at each side, which are attached to the nuts holding the swing front. In this way the extraneous folds are drawn entirely out of the way. When old bellows are inclined to sag in the middle at a long extension, a couple of loops of extra length attached in the same way will go far to overcome the trouble.

The Education Of Assistants.

           Our title has nothing original about it, it has figured pretty frequently in the "Journal" lately, but as the question seems in rather a nebulous state, it is perhaps in order to inquire what it really means. In other trades it is not usual to employ the wide and comprehensive term assistant, but to specify the branch in which the employee is to be engaged. In letterpress printing, for example, we have compositors, linotype operators, machine minders, and warehousemen, and in each division a man is only expected to be proficient in his particular work; but in photography, except in very large establishments, this is not the case, and an' assistant is expected to be able to turn his hand to any job which happens to come in his way, or in other words, if the reputation of the studio is to be kept up, to be as good an all-round worker as his principal and a better one in some particular section. That there are such assistants we very well know, and the photographer who secures the services of one is to be congratulated.
           Now before starting any education scheme it would appear to be necessary to define the various classes of assistants and to set up some standard of proficiency for each. Another important paint to be settled is that of remuneration, so that a youth or girl entering the profession should know what wage can be looked forward to when he, or she, has qualified as proficient. Many things besides scientific knowledge and practical proficiency are called for in everyday work. We have known amateurs capable of turning out prints which would do credit to any studio in the kingdom, but their pace has been hopelessly slow, and no employer could afford to keep them. Nothing but practice in a busy place can give the necessary smartness, and it is a question how this is to be obtained.
           The old practice of engaging a juvenile as a sort of messenger and general helper with more or less opportunity to pick up knowledge of photography will obviously be out of the question under the new regime. Proper teaching should start at the outset, and it is difficult to see how this is to be obtained in many localities. Let us take the case of an intelligent lad living in a small country town who wishes to become a photographer. The only course that is open to him is to obtain work in the local studio with a man who can just manage to make a negative and print it sufficiently well to pass muster with a not too critical class of customers. When the lad begins to want a living wage he looks further a field, only to find that he is one of the incompetents whose existence we all profess to deplore, but who provide a source of cheap labour for the sweaters who, as in all other trades, are found in photography. If we are to have well-trained assistants there must be sufficient inducement for them to be trained in the same way as chemists, engineers, lithographers, or dental mechanics, by a proper system of apprenticeship or pupilage, supplementing their workshop practice with a part-time training in the scientific aspect of their work. The latter cannot be given in a house of business without serious waste of time, so that something on the lines of the Fisher scheme of education must be adopted, and it is for the masters to co-operate with the local authorities to secure this. But such a scheme is only workable with very young people; after the age of eighteen it is very difficult to find that readiness to assimilate knowledge that is natural to the schoolboy. It is easy enough to teach youngsters of fifteen to eighteen such subjects as elementary chemistry, optics, or even art principles, but if those three precious years have been wasted, the mind takes another turn, and learning becomes laborious. Moreover, a bad way of working is acquired, and this is often felt to be sufficient. There is now also the sex question to be considered, as a great change is coming over photography by the invasion of women into almost every branch. Are the assistants of the future to be male or female? Already men returning from army service are finding that situations are not so easily obtained as they had expected, and we look for still further developments in the same direction. Only a few years ago, and women were considered as greatly inferior to men as retouchers. What is the position now? The same thing going on in other branches printing, dark-room work, and even in studio operating - the only field in which male labour is unchallenged being that of outdoor work.
           Still, male or female, we must have assistants, and the initiative for their training must come from the master photographers. Their first problem will be to find instructors, the second to find a body to hold examinations and grant certificates of such a degree of proficiency that the holder can secure a standard, wage. In the organization of the chemists and druggists we have an excellent model. In this profession a youth enters as an apprentice, is given time for study, usually takes a course under a coach, and finally passes his minor and major examinations before he can hope to attain a position as a “qualified assistant.” One of the greatest factors in producing a shortage of good assistants is the ease with which a competent worker can start on his own account in a small wav. If we can offer such terms as will keep good workers in their situations we shall have accomplished much.

Practicus In The Studio: A Talk About Lighting.

           Lighting the sitter is one of the most difficult subject to discourse upon that could well be chosen, for so narrow is the margin between success and failure that it u not possible to give definite rules which will ensure the same results under different conditions; in fact, so far m this true that there is a legend that one successful portraitist abstains from having his windows cleaned lest the lighting should thereby be rendered to hard.
            Hearty very competent writer on the subject has recommended the study of lighting to be begun with s plaster bust, and with this I heartily agree. The only thing better would be to follow the example of Adam Salomon and have life-sized wax figures with hair and clothes complete. A life-sized bust is not an expensive luxury even in war-time, for I recently purchased one near Hatton Garden for five shillings. It was the head and shoulders of Gibson's Venus, and has not special pretensions to classical beauty; it is just a moderately good-looking young woman with her head well balanced upon her shoulders. Busts having the head in unusual positions should be avoided, as the lighting which might suit them will not be useful for sitters.
            Having got our bust, the first thing to be done is to give it a coat of buff or very pale terra-cotta distemper, so that the light values will be about the same as those of the living model. This u very important, as white plaster reflects far too much light for our purpose. The reason why I advocate the use of a bust instead of a living sitter is that the latter cannot keep still for the time required for study, and the student will quickly see how a slight movement of the head upsets all his plans for obtaining a certain effect.
            The bust must be placed on a table so as to be about the height of an ordinary sitting figure, and in front of a plain medium-toned background. It should be in such a position that a high side light falls upon it, the light being rather to the front of the object. In an ordinary span-roof studio this would mean that the dark blinds or curtains would be drawn over one end of the studio, both top and side, for about five feet The bust should be about three and a half feet from the end wall the next blind should be half-down and the next quite open; the side light is obscured up to nearly five feet from the ground, and is open for about six feet run. If we now examine the lighting we shall find it fairly round, but rather contrasty. This is all for the best, for we can readily see the effect of altering the positions of the bust, the blinds and the camera respectively. One golden rule, by whom originally written I know not, is that "light from the sitter's end of the studio gives contrast, while light from the camera end gives softness." I cannot too strongly impress this fact upon the beginner.
            In ordinary circumstances, if the lighting is too harsh, open more blinds over the camera end; if too soft, close them over the camera and open them near the sitter. This one rule is the key to simple lighting, and its application will prevent much floundering in the early stages. If we do not want to alter the blinds we may move the sitter; if she goes further under the dark blinds we get softness; if she comes forward we get contrast.
            Excess of top-light is the commonest fault in portrait lighting; but there are times when top-light is needed. A flat face with insignificant features calls for it, as Mr. H. P. Robinson says: "I think I should use a good deal of vertical light in taking the portrait of a Chinaman." If the sitter had strong features and deep-set eyes such lighting would be disastrous. We may now try the effect first of turning the bust to and from the light, and you will quickly see how the modeling of the face is affected. As we turn the nose to the light the further check becomes illuminated, while as we turn it away it sinks into shadow. I would ask you to remember that neither the camera nor the sitter is screwed to the floor, so that you can obtain the same position of the head, but with very different lightings, by turning it till the desired effect is obtained, and then placing the camera in the position whence you observed it. Always keep your eyes open for accidental effects of lighting, and note the sitter's position in the studio for future use; some of these "observed" lightings are much better than those carefully arranged. I have nearly always found that the effects obtained with dark blinds and clear glass only are rather too vigorous for the ordinary run of work, hence it is very desirable to have in addition very thin white blinds or curtains so as to diffuse the light a little and tone down the glaring effect of the nigh-lights. If there are no white blinds an ordinary circular head-screen covered with thin nainsook or pale-blue nun's veiling is very useful. The nearer this is placed to the sitter the softer will be the lighting, and vice versa. In studios which are so placed that direct sunlight falls upon the glass during any period of the day white blinds should be used to cover all the glass. I have worked in this way in a studio facing due west, on which the sun shone from 11 a.m. until evening. In such a studio we must not have too large an expanse of white-covered window open at once, or we shall get flat negatives.
            A point which should never be lost sight of is that the actual design or pattern of the studio is of no moment. So long as the light can be made to fall upon the sitter at the desired angle, ridge roof, single slant, top-light, high side-light will all give the same result if properly handled. Much more depends upon outside influences; trees, walls, other buildings all serve to modify the lighting and an arrangement of blinds which will suit the sitter in one studio may fail to do so in another which is differently placed.
            A lofty studio is not to be desired. I remember one clever photographer who said that he would work under a cucumber frame if he could. In a high-roofed studio the light is very difficult to control, as it is too far away from the sitter. Even, soft effects are easily obtained, but when any decided lighting is needed it becomes necessary to close all the blinds and to use the side-light only, and that only in a limited area.
            A few words on unusual forms of studio may not come amiss. When working in a studio which has top-light only, the sitter must be placed well back under the dark blinds, and plenty of light admitted from the "camera end." It is also often advantageous to turn the sitter slightly to one side of the studio and to work the camera close to that side of the studio, towards which he is looking, the background being, of course, placed diagonally across the corner. In a studio with a high side window only it is often necessary to place the sitter as close to the window side as possible, so as to get the effect of top-light. If too low a side-light be used the eyes are filled with light and look flat. What is sometimes called a "miniature-painter's light" is a high front light. This gives a very even, illumination of the face, but if properly managed there should be sufficient shadow and one side to avoid flatness. If it be desired to copy the lighting in an existing photograph or even a painting, if by a good artist, the spark of light in the eye forms a reliable guide as to the position of the dominant light. If this be high or nearly in the centre of the top of the iris, in the position say of 11 o'clock on a watch dial, it denotes a high front light, if in the position of 9 o'clock a low side light, and so on In some fancy lightings it may even be at 6 o'clock, which shows that the light comes from below.
            I will now deal briefly with screens and reflectors. The head-screen I have already dealt with as far as lighting the features is concerned, but it has other uses, such as subduing the light on white drapery. Nothing is more objectionable than to have a white dress brilliantly illuminated, making the face appear too dark and receding into the background. By use of the small head-screen this may be avoided, the shadow being cast where required. In some cases a screen covered with a thin open black material is useful, as it will cast a shadow without diffusing white light in other directions. Reflectors are usually relied upon too much; only when the lighting is nearly satisfactory but the shadows are too dark should they be introduced, and then not placed close up to the sitter. In this position they destroy all the modelling on the shadow side and give an unnatural appearance. It is unfortunately too common for the operator to make a hard lighting and then to use the reflector to even up the face. This is wrong, as it does nothing to subdue the over lighting on the other side. There is no need to be afraid of using a screen or white blind to soften the high-lights, as it does not cut off any light from the shadows which are still receiving front light and reflected light from the studio. If the same exposure be given with the high-lights screened the negative can be developed for the shadows without the high-lights blocking up.
            In conclusion, I would caution the tyro against judging lighting by the eye alone, the negative being the only test. The plate does not always see the sitter in the same way as the operator does. Some plates have a tendency to intensify the light, while others soften it. The lens also has a say in the matter, a short-focus lens usually giving a more brilliant negative than a long focus one does. This is partly due to scattered light in the studio, but it also seems to be caused by the distance between lens and plate. Naturally the operator will see that his lens is clean, his camera well blacked inside, and his dark-room light beyond suspicion before he starts work, or he is simply inviting failure in any attempt to secure good lighting.

PRACTICUS.

Lenses Fob Odd Jobs.

           Most professional photographers would be surprised if they were told that in the matter of lens equipment they were far behind many enthusiastic amateurs, but we believe that we are correct in making this assertion. The fact is, that the professional is rather apt to put all his eggs into one basket, or, in other words, to invest in a few first-rate lenses and to consider that he has done all that is needed. He selects lenses for the size of the plate he generally works, and, so far as it goes, this is quite correct; but he seldom has anything to fall back upon for any job which may require one of a different focal length. It is remarkable that this is more likely to be the case with the photographer of to-day than it was a quarter of a century ago. Then it was not uncommon to find an equipment of a complete set of portable symmetricals, twelve in number, ranging from three to, twenty-one inches in focal length, the first ten fitting the same flange and in many cases having the lens cells interchangeable, so that even a variation of half an inch in focal length could be obtained. There were also "casket" sets, usually not of the finest optical quality, but good enough when used with small apertures, which gave an even greater range at a very reasonable cost.
           The portrait man does not, of course, need such a variety of tools, but the man who is willing to take on any class of work frequently finds that he cannot do exactly as he wishes, and, what is more important, what his client wishes, because of his imperfect equipment. This state of things can easily be remedied at quite a small cost if it be borne in mind that a comparatively poor lens works nearly as well as an expensive one if it be possible to use a small aperture. Another point to be remembered is that with modern enlarging methods at our command it is not always necessary to limit ourselves to one particular size of plate, since, if we can get our subjects, it is easy to make prints of a larger or smaller size as may be required.
           Let us take a few examples of possible orders and how they may be executed, or, to be more precise, how such orders have been executed. An extremely wide angle view of a street scene was required to show the disadvantages which would result to a shopkeeper if a railway viaduct were put near his premises. No orthodox lens would give the necessary view angle, but by using a four-inch lens which happened to be at hand, a negative was made upon a whole plate, which did just what was wanted: it gave the width of the picture well defined, and when the top corners were blocked out a 15x12 enlargement was made which did good service in court. Now, how many photographers have a decent four-inch wide angle lens in stock! Yet it is not an expensive tool, and if not paid for by the one job, its possession helps to build up a reputation for efficiency which leads to future orders. Such a lens is not only useful for outdoor work, but for enlarging when only a moderate length of bellows is available. If it be necessary to take a mall head out of a group, a considerable degree of enlargement can be obtained directly instead of having to resort to a second enlarging process. Conversely, such a small lens is of great value for making reductions with the enlarging lantern. If a copy, say, an inch by three-quarters, or less, has to be made from a cabinet negative it is easy to do so.
           Going to the other end of the scale it is a rare thing to find a telephoto lens in the hands of the ordinary photographer; yet is a most useful instrument for many purposes besides taking distant views. We remember some years ago, when the original Adon was introduced, being told by a large firm who specialized in catalogue work that they had been recommended by an amateur to try a telephoto lens for the photography of small articles, with the result that they had greatly improved the perspective in very case to the satisfaction of their customers and their own profit.
           While comparatively cheap lenses of the old rectilinear construction are capable of doing much useful work, we should not recommend their purchase if funds permit of more modern instruments being obtained, for when a lens is being used for copying or in the enlarging lantern at an extension which is many times its focal length, a large aperture is of great advantage, the difference in luminosity between one having an initial aperture of f/6 and f/16 being very noticeable, and if such lenses are of the "convertible" type, giving two or three focal lengths, their utility will be increased. Still, before purchasing new lenses it is as well to take stock of what lenses are on hand, and to make a note of their focal lengths. If duplicates of any one size are found one should be sold or exchanged, so as to secure further variety.
           It may be found that although suitable lenses are available, there is no means of using them upon large cameras or enlarging lanterns, and it is therefore advisable to have them adapted to the flanges already upon such cameras. This can be done at the cost of a very few shillings, and in the case of modern instruments it is not necessary to part with the lens or large flange, as these will be of standard and it will only be necessary to mention the diameter. For a makeshift, a very good plan is to cut a hole in a piece of card so that the lens thread will just go through, securing it by screwing on the flange at the back, the card being attached to the camera front by means of four drawing pins.
           Supplementary lenses of the Planiscope type will often prove useful, to shorten the focal length of lenses which will not give the desired angle or magnification, but it will usually be found necessary to work at a very small aperture when these are used, as the corrections of the original lens are upset. However, for this class of work speed is usually not necessary. A makeshift Planiscope may be made by attaching an ordinary small single lens, such as the front of a small portrait lens or one of the combinations of a rapid rectilinear, by means of a cardboard ring This sound rather crude, but we have known it to be done with success.

Assistants' Notes - 1

Books on Colour.

           Assistants who mean to make photography their profession should look into the question of colour, as pictorial art of the future will be intimately concerned in the study; some authorities-particularly those connected with the vast textile industry declare the future is bound up with it. Students of painting are bidden to study nature secrets, but students of photography will find the scientific side profitable and to their liking. Since 1835 over sixty books have been written, a fourth of that number being published in London, a fifth in New York. The Americans, by their productions of the last ten years, promise to surpass us on all points – by numbers, high prices they command, complete range of subject, interest, and research. As all books of recent yean seem to be written round Rood's "Modern Chromatics,” students will do well to commence with that treatise, as it contains valuable information, clearly written, well illustrated with woodcuts and diagrams, but unfortunately has no colour plates to assist the text. This book having passed through many editions, a clean secondhand copy is more often seen than any other, and is worth looking out for.- BURLINGTON

A Reliable and Permanent Method of Intensification

           Many photographers would be glad to banish mercury from their dark-rooms if they could find a satisfactory substitute for it. Those who use the mercury intensifier know that they cannot depend upon the negative being any use in a year or so, and, although they have tried the chromium method, the danger of yellow stains has caused them to go back to the old process again.
With papers of the "Cyko" class it is essential that the negative should be free from all stain, or the time of printing will be unduly prolonged. The following method of intensification has been in use in a well-known North-Country studio for some considerable time, and may, be depended upon to be stainless action and to give an absolutely permanent result.
           Make up lour solutions: -                                  Water
           A. Potass. bichromate ………………………150 grains 10 ozs.
           B. Potass. bromide ……………………………400 grains 10 ozs.
           C. Hydrochloric acid (pure) ………………200 drops 10 ozs.
           D. Potass. metabisulphite …………………2 ozs. 10 ozs.

For use, take equal parts of A, B, and C. Blench and immerse (after a brief rinse under the Up) in D solution until the yellow lain is completely destroyed. The negative is then re-developed in any non-staining developer without bromide, Azol or a paramidophenol mixture being especially suitable.
           The method is equal to mercury in every way, with the additional advantages of being permanent, and that it is not necessary to eliminate all the hypo in the film previous to bleaching.
           Bay pure chemicals, mix in the proper proportions, and use as directed above, and you cannot fail to get good results. - J. M.

Advertising by Airbrush.

           As American soldier, by trade a sign-writer, was recently making comparisons between this country and his own on questions of advertising, and. although we pointed out that the war had stopped experts here as well, he pointed out the difference between the stylish window tickets of City tailors, shaded in colours by the air-brash, with the old-fashioned printed silver letters on black in a studio showcase, and he could see no evidence that we had ever made nee of striking designs and methods as are tried in America. He criticized photographers, and guessed that the majority tad an artist and an airbrush on the premises, and yet they do not make use of the instrument at all for stenciling through and shading round a design, or even a little ground tint to letters calling attention to the studio's particular style, or inventing an attractive price-list panel for the window. American schools, such as the Detroit School of Lettering, use the airbrush largely for advertisement purposes, believing in colour and design as u means of arresting the eye. - BURLINGTON

EX CATHEDRA: Low-Priced Trade Work; A Lecture on Photography; Focussing Sharply; Patent Specifications.

Low-Priced Trade Work.

           In a business such as photography, in which the goods sold to the public exhibit so wide a range of quality, it is, of course, natural to find a similar range of quality in the work done by trade firms for photographers. In both cases the quality is more or less accurately reflected in the price which is charged. A consideration of these facts should, we think, provide tie answer to those who now and again urge upon our publishers that they should exclude the very low-priced firms from our advertising pages. An order for enlargements to one such firm may have been executed in what the disappointed maker of the negatives angrily calls a “disgraceful" style, on the strength of which, and without showing either the enlargements or the negatives supplied for them, it is protested that the firm should not be allowed to advertise its offers of service. As we have said, a complaint of this kind can only be made in the absence of a comparison between the price which has been paid and that charged by firms of the first or even the second grade. Probably the chief difference between low-price and high-price firms - a more essential difference than poorer materials and cheaper labour is that their scale of prices does not allow them to repair defective work by doing it again. They send their first production unless its defects are too gross even for their standard, and hence the result is very largely a matter of chance. Like the little girl and dependent on the negative, it may be very, very good or it may be horrid. If it be the latter, the purchaser must surely think that he could hardly expect anything else at the price. His case is paralleled by that of anyone who puts money in a high-yielding investment: he is buying something cheaply priced, and he takes his chances on it. No doubt the advertiser announces that his work is first-class, but then what advertiser does not?

A Lecture on Photography.

           Perhaps it is a welcome sign of greater general interest in technical and scientific matters, perhaps the result of the searchlight prominence of photography in the war, but we have lately received quite a number of requests that we should name the book to be recommended to anyone anxious to deliver a popular lecture on photography. The fitness for his purpose of a would-be lecturer who finds it necessary to put the question may be doubted, but at any rate the inquiry exhibits a praiseworthy desire for information, and doubtless there are many with a thorough practical acquaintance with photography who are not too self-confident to see that much more is demanded of a lecturer on the subject. For such as they a book which provides, a serviceable basis of information is Mr. Chapman Jones's "Photography of To-day," a volume which reviews pat and present photographic processes in a popular yet scientific way. On the very earliest history of the art, that is the work of Niepce, Daguerre, and Talbot reference may be made to a series of papers which ran through “The Photogram” for 1900. There are one or two issues of “The Photo-Miniature” which will usefully provide material, viz. those on "Who Discovered Photography”, “Colour Photography," and "Aerial Photography,” and as a means of faking a bird’s-eye view of the successive of photographic progress there is the monograph “Photography, Past and Present” issued as an illustrated supplement to the Diamond Jubilee Number of the “British Journal."

Focussing Sharply.

           In focusing originals, such as paintings, in which the absence of definite outlines presents a difficulty, most photographers make use of a small printed card placed against the surface of the original in order to provide a workable test object. But perhaps it is not so generally recognized that different types of lens require different treatment in order to obtain the best results. As a rule, rapid rectilinears and other lenses possessing greater or less roundness of field give the best average sharpness when the test object is placed so that its image falls about midway between the margin and centre of the field. With most anastigmats it is best to obtain the greatest sharpness in the centre, and the margins will then frequently be sharper in the negative than they appeared on the screen. With all types of lenses great assistance can be given by a judicious use of the swing-back, both vertical and side movements being employed as needed. This is particularly the case when using a portrait lens at its full aperture; a swing of the back will allow of the same degree of good focus over the plate as could, be obtained by a smaller stop. The method must not be abused, particularly when a short-focus lens is being used, otherwise the size of hand and feet in the sitting figure will be unpleasantly exaggerated.

Patent Specifications.

           A correspondent who addresses a query to us raises a point which no doubt is now and again in the minds of many other readers of these pages. It is a matter of common remark that the published specifications of alleged inventions to which patent protection is granted are often things which are as old as the hills or, on the other hand, bear on the face of them certain practical disabilities. But the explanation lies in the fact that the preliminaries in the way of search which are carried out before the granting of the patent extend, not to books and periodicals where the invention very likely has been published, but only to patent specifications themselves issued during the period of fifty years prior to the date of application. Moreover, the Patent Office is not concerned with the efficiency of an invention. It takes the applicant's word for its merits in this respect. Apart from its search in prior specifications its work is not very much more than a registration of the description of the invention and the claims made in respect to it. The questions of efficiency and of prior publication are left to be the subject of investigation in a court of law in the event of any action being taken as to infringement. While there are thousands of existent patents which have not been the subject of this legal inquiry, it is nevertheless true that a patent has not received absolute certification of value until it has been examined in the Courts. Inventors of photographic appliance: should not therefore set too high a value upon the fact that they may have teen granted a patent for a particular appliance. Nevertheless, it is a wise and not very expensive precaution to spend, say, the mutter of five pounds on obtaining protection for any invention before offering it for sale to a commercial firm. The patent rights can then be disposed of, and the co-t of maintaining the patent defrayed the purchasing firm if such is considered advisable.