Human Lifestyle

I got up early and had a bath and hair wash in last-night's hot water off the stove. Then took the children to school.

Sight and the Photographer.

           IT goes without saying that sight is the most important bodily function from a photographic point of view. One might imagine an armless, legless, deaf or dumb person performing some job or other connected with the business, and even one with deficiency of intellect might posses some little photographic skill, bat a blind photographer is impossible.
           It follows that a photographer's eyes, good or bad, should not be neglected, but accorded at least a modicum of intelligent consideration. A good many pros. hold the belief that the practice of their craft is in itself sufficient ultimately to damage the sight, and judging by the number of workers one meets whose eyes are not so good as they might be, the belief seems reasonable. On the other hand, there are craftsmen of ripe age whose sight is still perfect in spite of yean of hard work. The fact is that photography can – not must – damage or even destroy the sight of anyone engaged at it, the damage usually being brought about by circumstances many of which are in themselves inconspicuous and therefore unsuspected.
           These circumstances depend on the nature of the work, each branch of the business having its own peculiar sources of possible eye strain. In the studio the eye may suffer from constant straining at a too thick or coarse focusing screen, or focusing with the lens stopped down. This is a small thing, but in a very busy shop when the operator may be behind the camera for bourn at a stretch, the strain will tell. Where roach focusing has to be done, as much light as passable should be allowed through lens and screen, and the work done smartly. Indecision ceases strain, and does not improve the final definition of the picture.
           The continual itching from abort to long focus, occasioned by looking first at the sitter and than at the screen, may tire an eye but if the eyes (and the general health also) are this should prove more of an exercise than a strain.
           Working with artificial light, an operator may damage his sight by allowing the light to fall directly on his face too often; in other words, by looking long or often at the lamp. Continual witching on and off from full light to semi-darkness, as also going in and oat between studio and plate-changing room, will leave its mark on the sight if carried on to a great extent. The moral here is to keep a fair amount of light in the studio all the time, and have an assistant changing. The latter can keep his or her gaze away from the bright end of the studio without any trouble.
           In the dark-room the red or yellow lamp is often blamed for tired or failing eyes. This is not strictly right, though the position and strength of the coloured light is very often to blame. A lamp should never be in a position to sand direct light into the eye when working, and for this reason a hanging lamp, shedding all its light downwards, is to be recommended. The strength of the light should be as great as the sensitive materials will permit. With regard to the printing room, I would say to those who can please themselves: Discard bromide for gaslight, have as much light as you would in your drawing-room, and be comfortable.
           Where yellow or red light is compulsory all walls should be painted vary light: it will obviate much eyestrain in groping about for things which are invisible.
With printing and retouching direct light is mostly used, but in neither case does it – so far as my experience and observation go hart the eye to the same extent as in the case of the dark-room lamp. The difference is this: in one case the eye is working with the image supplied by the direct light and nothing else, in the other the direct rays are worrying the eye and distracting it from its work. This can continue for a long time without the victim being aware of it, even though the eyes and the work may be suffering.
           For retouching, the use of direct light, however, is not compulsory; many workers prefer to work against a white or tinted reflector, and one retoucher I know claims that this practice is repairable for his sight being as good as it was twenty years ago. Retouching with weak light, particularly if the negative is yellow or dense ceases eye strain, while the remarks on dark-room lamps apply also to extraneous light near a retouching desk. Working on very small beads is apt to be trying, and for this a magnifier may lessen the strain, bat it should not be used habitually, otherwise it may become an indispensable crutch.
           Spotting and working-up require sight that if perfectly free from automation, and when done by anyone whose sight is not normal, and not corrected by glasses, this work will greatly aggravate the weakness. At the slightest sign of strain the lighting conditions should be examined, and if not at fault astigmatism should be needed and the eyes tested. Spectacles, however, are not likely to cure bad light; they will correct the vision and so do away with strain, but that is all.
           Before going any further it may be as well to say that this article does not pretend to deal with its subject from any but a purely photographic standpoint. The many defects of vision caused by such things as nerves, bad blood, cigarettes, etc., are not within my scope, and when a photographer's eyes give trouble it rests with him or his doctor to decide whether his craft is to blame or not; it is always possible that some outside influence is causing the mischief. At the same time, a few remarks on the care of the sight may not be out of place. Tired or overworked eyes can be benefited by bathing, and any chemist will make up an eye-bath cheaply. The simplest and safest of these is boric acid.
           Sight can be greatly improved by country walking, particularly in districts where long clear views prevail. In my own experience I find nothing to equal daily gazing at landscape the foreground of which is mostly green, with distant planes stretching to far off mountains. Unfortunately, we cannot always enjoy this kind of cure for tired eyes, but in any case and at all times it pays a photographer to care for his eyes, even if it means a little extra trouble. This applies particularly to young workers. In the vigor of youth details are not so readily noticed as they are in alter years, and a young enthusiast may go on working in conditions which are bad for the sight without worrying until the mischief is done. Years after it may cost a good deal to undo what a little forethought could have prevented. – THERMIT.

Complete Development

            The maxim which is rightly emphasized to makers of bromide prints, namely, to develop thoroughly, is one which even now, although it has been repeated over and over again, is largely disregarded. Neglect of it is one of the chief causes of unsatisfactory quality in sepia-toned prints, the results of toning an image which has been rapidly and, therefore, superficially developed being greatly inferior to those in which development has been carried more deeply into the film. One rule which has been given for the guidance of bromide printers is that the time of development should be at leant three minutes, and exposure adjusted accordingly in order that the print at the end of this period of development should not exhibit the effects of over-exposure. But papers and developers having their particular idiosyncrasies, perhaps a more usefully applied rule for discovering whether prints are receiving this "full" development is to immerse half of s print only in the developer, and after the expiration of, say, half a minute to allow the developer to act upon the whole. If, then, development can be continued so as to yield a satisfactory print which does not show a difference between the two halves, the worker may be satisfied that his development u of the required fullness. On the other hand, a difference between the two halves will indicate that exposure can be advantageously cut down.

Colour of Second-hand Lenses.

            Those who are baying secondhand lenses will do well to give the question of colour some consideration. As is well known, long exposure to damp or atmospheric conditions lead to discolor the glass of the lens, or cause the balsam cementing the components to deteriorate with the same result. Some secondhand lenses that we have seen suffer from this very badly, the glass having quite a yellow tinge, in others, though existent, the defect is not so apparent, but if present the marked aperture of the instrument does not represent its actual working speed. We had one inch lens that when examined in a casual way showed little or nothing the matter, but when placed against a sheet of pure white writing paper a slight discoloration was at once noticed Slight though this was, it had a marked slowing action when using ordinary plates, though when orthochromatic emulsions were employed this to a large extent disappeared. Those having such instruments will do well to send them to one of the firms advertising in the advertisement columns of this Journal for repolishing or recementing of the glasses as the case may be, while if buying a secondhand instrument prospective buyers should be on the watch for a defect, which, though it might easily peas unnoticed, reduces the actual value of a lens very considerably. This discoloration is perhaps more frequently met with in the older instruments than in the modern anastigmats, unless these have been very much exposed to bad conditions, but it is a condition of things that all owners of good cemented anastigmats will do well to guard against.

Camouflaging the Camera.

            We commented recently upon the use of the small camera in certain branches of photographic work where its advantages may be turned to good account. A further instance of its value as a supplementary instrument in the studio was told to us the other day by a professional friend. He was commissioned to make a portrait of a child of whom previous experience had taught him that, however pleasing might be the expression on the little sitter's face, it instinctively froze directly the operator made a move towards the camera. The studio instrument was prepared in the usual way, and in front of it was placed a table with piles of books, etc., very carefully arranged to conceal a previously focussed vest-pocket camera, with its shutter set ready for an exposure. The usual attempts were made with the studio instrument and with small hope of obtaining a satisfactory picture. The operator turned away rather disgusted. Almost at once the little sitter was herself again, and casually, as it were, turning to the table the operator pressed down the shutter release of the vest-pocket camera, covering the action as if by taking up a book. As was expected, the exposures made with the studio camera were failures from the point of view of expression, but the small camera yielded a lifelike and pleasing portrait. The negative was carefully enlarged, and the result was an order for some dozens of prints. The idea of camouflaging a small camera should prove of value to those photographers who have to take portraits of nervy sitters, since the exposure may be made at a selected opportunity without the sitter being aware of it. Such a plan should help in overcoming many a difficulty in this respect. Though the negative is small, the quality can be of the best, and the resulting enlargements with a little working-up should give no indication whatever that they are not contact prints from large-sized original negatives.

Varnishing Negatives.

            Few photographers at the present time varnish their negatives, nor when ordinary bromide printing or enlarging is to be the medium is this course really necessary. But when a number of P.O.P. carbon or platinum prints are required from one negative, and the printing is done in the semi-open air for the most part, in damp weather it is a wise precaution to give the negatives a coat of ordinary cold varnish. Many present-day operators, however, find a great difficulty in getting an even coat of varnish over the entire plate by the ordinary method, and if this is not done there is a tendency for the varnish to dry in ridges, which means, of course, corresponding markings on the prints. Varnishing negatives by flowing the varnish on and tilting the plate at various angles until the whole is covered, and then draining the surplus back into the bottle, is an operation that requires a certain amount of skill, which can only be obtained with practice. We have for some time past varnished our negatives with an ordinary camel-hair (or hog-hair) brush. The exact kind is not very important, provided that it is well made and free from loose hairs. For this method, though not strictly orthodox, we may claim that it is comparatively easy to put a light but even coat of varnish on the film. None of the varnish need be got upon the back of the plate, and negatives may be very rapidly treated. Care should be taken not to get the brush too full of the varnish, or uneven coating may result. To those who have had no experience of varnishing negatives this alternative method may be recommended, although the essential feature of it is that a thin coating is rapidly applied.

           IN many localities, notably in the London district, the state of the atmosphere has left much to be desired from the photographer's point of view. Not only has there been an actual deficiency of light through the presence of more or less yellow fogs, but there has been great difficulty in securing brilliant negatives on days when the light was fairly good, because of the general haziness of the atmosphere. Many photographers suffer from this fogginess without quite being aware of the actual cause of it. A simple experiment which will show in a rough way how much fog is present in any room at various distances can be made with the aid of two ordinary black velvet focusing cloths, velvet being chosen because it has leas reflecting power than any other material in ordinary use. One piece of velvet is crumpled up so that some parts produce deep shadow and put on a table in the position usually occupied by the sitter. The operator then stands by the camera at the distance at which a full-length portrait would be taken, and holds up the other about a foot from his eyes so that it half covers the piece on the table. If there is any appreciable amount of haze present he will find that the deep shadows on the distant piece appear quite grey in comparison with those on the piece which he is holding, and at once finds an explanation of the flat negatives which he has been obtaining.
           Having established the existence of the fog, our aim is now to minimise its effects, and there are many methods by which this end may be partially attained which, when put together, result in a substantial improvement in the quality of the negatives. In the first place, the studio windows should be kept clean, so that as small an area of glass as will give the desired lighting will be needed to obtain short exposures. By thus closing out all unnecessary light we reduce the general illumination of the fog and get a much brighter image. This can perhaps better be seen when working with artificial light. If we build the lamps in with screens or backgrounds so that the light falls upon the sitter only and none reaches any other part of the studio, there are only three or four feet of fog to work through, while if the whole of the studio is illuminated the amount is greatly increased.
           In foggy weather the lighting of the sitter may be more concentrated than is usually necessary, as a more vigorous negative will then be obtained, and printing can be carried on until the shadows are of sufficient depth. Windows become coated with smoke in a day or two in the winter and act as undesirable diffusers, so that it is advisable to clean at least the panes which it is intended to leave unscreened.
           A fairly warm temperature and good ventilation tend to reduce fog and to clear it away quickly. We have often noticed that a room or studio has remained foggy long after it has become fairly clear outside. When the necessary power is available, an electric fan will do much to establish a current of air, which should be directed towards an open window or door. A proper exhaust fan fitted near the roof is the best form, but the portable ones are of considerable value.
           We have already pointed out how the effect of fog may be reduced by cutting out all unnecessary illumination. A further improvement may be made by using a lens of as short a focal length as possible, though not so short as to introduce distortion. Where sufficient length of studio is available, it is now common to use sixteen or eighteen-inch lenses for all-round cabinet work, and it is quite good practice in clear weather. But at other times a tea or twelve-inch lens will be found to give much brighter pictures. As a matter of fact, many photographers have found this out without knowing the reason, and attributed the improvement in brilliancy to some other property in the lens than its focal length. Whatever lens is being used, it should be kept clean. Lenses will get as dirty as windows do in a smoky atmosphere, and will then yield flat images in the clearest light. If a lens has not been kept clean it is interesting to take a negative with it before cleaning and one directly afterwards. In most cases the contrast will be striking. Lenses should be cleaned carefully, a vigorous rob with the corner of the focussing cloth is not to be recommended, as such treatment soon "greys" the surface. An old worn handker-chief, kept in a box free from dost and grit, should be used. If there is a greasy deposit from town smoke, a single drop of pure alcohol may be applied on a tuft of cotton wool, and then the surface quickly polished with the handkerchief.
           Although we are opposed to all “tinkering” methods of development, the judicious use of bromide upon exposures which have been made under adverse conditions is quite permissible. To describe the action of bromide in popular language, we may say that, when used upon an over-exposed or foggily lighted plate, it allows the high-lights to get a start before the shadows begin to develop. If the plate be developed right out this advantage is lost, but as most portrait negatives do not reach this stage there is a decided benefit to be obtained by the use of bromide in the cases we have mentioned. It is necessary to add the bromide to the developer before immersing the plate. Once development has started it is of little, if any, effect. The character of the plates used should also be taken into consideration. Some brands tend to give brighter results than others. These should be chosen for foggy weather, as, although the scale of tones may not be so long, the resulting print is more satisfactory.

           In no respect does the modern style of studio differ more From its predecessors than in the matter of accessories, and we might treat the former in the same way as did the writer of a book on Iceland. A chapter was headed "Snakes in Iceland," and the chapter consisted merely of the words, “There are no snakes in Iceland."
           When we speak of accessories it recalls to the old operator the wonderful combination sets in papier mache on a wooden foundation which gave pedestals, balustrades, stairs, bridges and a host of other things as they happened to be arranged, or the equally wonderful pieces of furniture which professed to represent a piano, a writing-table, a bookcase, and a seat, and deceived nobody. Then we had rocks, stone walls and loose boulders which were sometimes useful, not to mention ships masts, boats, and swings. These have now, happily, found a rating-place in the lumber-room or have helped to relieve the shortage of coal in these upside down times. Still one cannot but help feeling that the accessories themselves were not alone to blame for artificial-looking pictures, the unintelligent and mechanical way of using them being equally to blame. I believe it to be possible that we shall again revert to the use of more accessories in the true sense of the word, when someone finds it necessary to be “original” and to produce something to relieve the severe simplicity of the head and three-quarter length portraits which are now the vogue. The modern portraitist is not likely to fall into the errors of his predecessors, as be has learned to concentrate the interest in his nictures by subordinating unnecessary detail and would not think of making a negative in which the surroundings were as brilliantly and as sharply defined as the figure itself. Although they are somewhat out of favour at present I must confess to a liking for full-length figures, and it is difficult to get these well balanced without introducing something to give the needed spot or mass of light and shadow which makes the composition complete. This is, of course, widely different from the old practice of building a samba of plants and vases round a lady’s figure, so often done by the byegone masters of our art.
           A safe principle for the guidance of those who have to equip a to follow the advice of Ruskin and to have “nothing except what yon know to be useful or believe to be Beautiful.” Do not buy settees or chairs which no sane person would ever admit to a dwelling-house, but select every piece or furniture, whether intended for the studio, the reception-room or even the dressing-room, with a view to its suitability for inclusion in a picture sooner or fact. Variety, it his been said, is the spice of life, and variety in your work can be more easily secured if there is an ample choice in the matter of furniture. You will then steer clear of the error made by en American photographer whose confession I read a few years ago. He specialized in children's portraits, and when the twisted wicker chairs and settees were introduced invested in a fine specimen. Needing a new window display, he made a large canvas-covered panel, and fixed upon it a score or so of his latest and best productions. It was set up in the window and he went outside to judge the effect; when he viewed it he said that all he could see was twenty wicker settees with babies on them. A sadder and a wiser man, he went inside and promptly dismantled the show from which he had anticipated so much.
           Much of the charm of "home portraits" is due to the natural posing and the judicious inclusion of furniture and ornaments which are associated with the sitter in the minds of his friends. A scholar taken in his study appears more at homo than he does against a plain dark background, and in the case of people who, as an old friend of mine said, "are more distinguished by their facial peculiarities than by actual beauty," there is a real advantage in having something beside those "facial peculiarities" to rest the eye upon. In studio portraits therefore we should endeavour to reproduce the homo atmosphere as nearly as possible and to avoid giving the impression that the whole thing is a make-up. If it be desired to make a picture of a man at his writing-table, the general idea seems to sit him at a small polished table with one or two pieces of paper and a small ink-bottle and pen borrowed from the reception-room. Such an arrangement is little better than the Oriental method of arranging theatrical scenery, in which one painting does for ill the scenes, with the addition of a label to tell the audience whether it is a palace or a forest.
           When selecting chairs or settees they should be chosen not for the beauty of their design when empty but for their appearance with a person seated in them. It will frequently be found that the arms are too high or that the curves are such that a graceful pose, especially of the forearm and hand, cannot be obtained. Many chairs are far too low in the seat and have either to be made up with loose cushions or by fitting rather high castors to the legs. It is, however, necessary to have some low chairs for short people, but with ordinary-sized sitters a better pose of the shoulders is obtained by using a chair rather higher than usual. Settees are best of normal height, as in them a more lounging pose is usually wanted, so that all that is necessary is to avoid the special photographic patterns, except those of the garden-seat pattern, which are useful for sketch or outdoor effects. That much-maligned article the pedestal has had its day: it was hard-worked and has earned a rest. It has a useful successor in the flower or vase stand, which is very handy with standing figures, which would look a little lonely without it. It should never be used for the sitter to lean against, but with ladies portraits may be used to support a bouquet or a vase of flowers which the sitter is arranging. It may also be used to hold the busby or helmet of an officer in full dress, to avoid the necessity in the hand or omitting it from the picture, to both of which there are serious objections.
           Children’s portraits permit of the use of many simple accessories, especially for outdoor effects. I made a very useful tree-stump of a lard bucket carefully covered with virgin cork, so as to give the effect, of living bark, the lower ends being well spread so as to appear like roots. This with a cylindrical hollow "log," covered in the same way, afforded many excellent poses and did not look artificial. If the cork had been stuck in anyhow the things would have been useless. When working with these or other outdoor accessories a pail of coarse sawdust, the dirtier the better, is a great help. If a painted floor cloth be laid on the floor and the sawdust it, it looks like sandy earth and will show foot-marks, while it can be piled round the bases of such accessories as I have mentioned.
           A baby-holder is an accessory which should be in every studio that is not exclusively devoted to adults. It may either be of the American or clip variety, in which the child's garments are caught in clips' attached to an upright post, or it may be like a triangular seat with a low bark and a hole through which the child may be held by a person behind. I have found a broad tape, which could be passed round the child's waist and fastened at the back of the holder, a very useful addition. Such holders are, of course, only intended for babies who can just sit up, and could not be trusted in an ordinary chair; besides, it permits the feet to be shown nicely.
           Although I am more inclined to class them with apparatus, certain studio appliances are often called accessories. The head-rest is one and one which I should be sorry to dispense with. Some care is necessary in choosing and handling this instrument. In the first place it should not be heavy, and in the second place it should be simple. What is needed is a support which can be quietly placed behind the sitter (or usually slander), and adjusted so as to give the necessary steadiness. I may say that I rarely place the rest to the head, finding the shoulder or lower part of the neck to be a better position and less embarrassing to the sitter. The number of plates which are wasted on standing poses through "moves" by photographers who consider the head-rest out of date must be enormous. All the moving parts should be kept, like a rifle, bright and oiled where necessary, so that there is no jerkiness in action. Another necessary which I consider indispensable is the head screen. This needs no description, but the covering demands a few words. Most head-screens are covered with a sort of lawn, and this is generally useful; I have also tried light blue nun's veiling, nainsook, and tracing-cloth, as well as butter muslin: these all have different light-arresting powers, and the user must choose for himself if he does not find the stock covering to his liking. A black gauze is sometimes used when it is desired to cut off light without diffusing it. Such a screen is very useful for toning down white draperies without losing the modeling. The reflector also needs no description. As far as its qualities go it should be light in weight, not too large, and capable of being adjusted to various angles. As a rule the surface is too light when purchased, but this defect soon disappears. When the surface gets very grey the material should be, washed, but if it cannot be readily detached from the frame it may have a dressing if Blanco, a sort of pipe clay used by soldiers and for tennis shoes.
           To revert to our original subject of accessories which appear in the picture, I would point out that modern printing and enlarging methods offer such opportunities for control that many of the old negatives which gave meretricious results in albumen or gelatine-chloride would give quite artistic prints upon rough paper with the sharp offensive lights toned down. Uniform sharpness throughout the negative is no longer considered as desirable, so that any falseness of texture in the accessories is not shown in the finished picture. Finally, do not overcrowd your composition; do not use more accessories than are needed. If not needed, do not use them.

PRACTICUS.

[We are glad of the opportunity of publishing the second of the annual reports on progress in photographic manufacture which has been issued by the Society of Chemical Industry. The author is again Mr. B. V. Storr, M.Sc., of the. Ilford Company, to whom students of the technical and scientific side of photography will feel indebted for his analysis of what has been published and accomplished during the period under review, that is to say, the year 1917. We should point out that the reference "J" which figures frequently in the footnotes is to the "Journal of the Society of Chemical Industry." It will, of course, be noted that the report is one which had been completed some considerable time ago. Apparently it is not possible for the Society to bring these reviews out closer to date, although we should have thought that less than a year might be allowed to elapse before the completion of the reviewed period and the publication of the report, - EDS. “B.J.”]

           APARY from work on the production and perfecting of a antisfactory colour cinematograph process, it is probable that the chief photographic effort in the past eighteen months has been towards the improvement of methods particularly adapted to problems of the war. Exactly what has been accomplished in this direction is not yet disclosed to the general public, although some indications have been given in the form of special photographs such as those shown at the last exhibition of the Royal Photographic Society.
           On the whole the general manufacturing conditions have been getting gradually more and more difficult, although in some directions there has been an easement. Bromides, which reached a maximum price of about 25s. per lb. in 1816, have settled down again to about 5s per lb., while silver, which reached a record price of just over 4s. 6d. per os. troy, has dropped again to some what nearer its normal price. Gold chloride, on the other hand, has increased in price by about 25 per cent. Gelatine and all kinds of paper have been getting steadily scarcer and dearer, and owing to their own particular circumstances the manufacturers have found difficulty in maintaining their former standard. The condition of the glass market has compelled manufacturers to make use of renovated negative glass. The general effect of the entry of the United States into the war is not yet fully evident, but it appears highly probable that supplies of some of the raw materials will be still more restricted.
           The general position on some smaller though essential points has improved greatly. In addition to metol substitutes, metol itself is now being produced in this country as well as p-aminophenol, which latter is also being made in Canada; in Australia the manufacture of pyrogallic acid and amidol has been undertaken by a department of the government. The position in enemy countries is not known with certainly, but the patented process of Pape to resuscitate old developers by the addition of alkali is suggestive. Shering improves baryta-coated papers by a farther coating of albumen, and Luppo-Cramer makes the suggestion to improve packing papers by impregnation with manganese dioxide.
           The production of sensitizing dyes to replace those in general use before the war has been successfully accomplished by W. J. Pope, under whose direction are now being made, for Ilford, Limited, sensitol red and green (German punacyanol and pinaverdol) and a new sensitizer, sensitol violet, in addition to erythrosin and a number of dyes used for making photographic light-filters. These are being need both in this country and in the United States.

Negative Processes.

           There is little of actual progress to record in negative processes. The attempt to increase the effective speed of X-ray plates is being made in several directions, but no serious advance can as yet be reported. Baker increases X-ray speed by the use of two intensifying screens, one in front of the film, very transparent to X-rays, and one behind the film less transparent; Edwards for the same purpose proposes to coat celluloid film on both sides with emulsion. Paris and Picard have extended their patent with respect to phosphorescent substances to include the use of phosphorescent zinc sulphide as a substratum screen, a film of gelatinous alumina being precipitated on the sulphide to prevent contact with the sensitive coating.
           La Rougery has patented the production of a special negative paper by high-temperature calendering and pressure and Hudson the process of using an ordinary white paper or card for negative purposes, prints being obtained by reflected light. Sosna and Biedebach have extended their list of dyes used to prevent dark-room fog. etc., to include phenolphthalein, which turns red in alkaline developers – a process very similar in principle to the old method of using a dye in the developer.
           Several of the processes of manipulation have received considerable attention. Crabtree, of the Kodak Research Laboratory, has a paper on development high temperatures such as are frequent in tropical countries. The chief hardening agents are formalin, alum, and chrome slum, which may be employed before, during, or after development; the method recommended is to use a p-aminophenol developer, which causes very little swelling of the gelatine, followed by a plain fixing bath, a chrome-alum fixing bath, or a formalin fixing bath according to the temperature. In the experiments 95°F. (35°C.) was taken as the maximum which need be considered. An interesting method of using a two-solution developer is given by North, who treats the plate first with the solution of reducer and then with the alkali, a method which has the effect under suitable conditions of restraining the denser parts of the image and allowing full development of the light tones. p-Phenylenediamine or quinol with ammonium chloride is recommended as developer hen fineness of grain is desired, the slight solvent action of these substances on the silver salt assisting in this direction; Koch and du Prel, however, attribute the effect to a development of part only of the silver bromide granule. Brewater patents the use of the same developer, combined with nitrate, for development of a wide range of exposures; Loth substances were, of course, known already as preventives of reversal when present in the film during exposure.
           Ross, for the production of stellar images, recommends the use of a quinol and alkali hydroxide developer as giving clean-cut images, a practice in agreement with that of process workers. In this connection some experiments of Campbell and Turner are interesting. The former, by measurements of spectrograms, obtained smaller readings for the separation of pairs of lines than were given by Rowland's tables. The latter got a similar effect in crossed images of a reseau when the lines approached within a certain limiting distance and suggests some mutual effect between the images; it would be interesting to know to what extent this effect could be explained by a disturbance of the mass centres of slightly separated images by reason of the overlapping of the fringes between them, and also whether an actual slight displacement of the lines towards one another is produced in the drying of the plates by reason of the hardening of the film between the lines as compared with that on either side.
           Hechstetter has patented a combined developing and fixing bath which contains thiosulphate and glycerine, with citrate apparently as restrainer.
           The general question of fixing and washing has been examined by Elsden and Warwick. The former determined the rate of removal of thiosulphate from a gelatine film by successive washings and found no evidence of adsorption. The actual time necessary for complete removal will of course depend upon the amount of thiosulphate present, but chiefly upon the rate at which equilibrium is attained between the film and the washing water, this being a function of the nature of the gelatine film and temperature. Warwick found the same general rule to apply and examined also the behaviour of papers, where the absorbent base complicates the problem, and the method of washing in running water. In a further paper Warwick considers the rate of removal of the silver salt by thiosulphate, the normal law being again followed. The rate is dependent on the strength of the hypo solution, a maximum being reached at about 40 per cent, and a zero rate at saturation point. He used a silver sulphide tint, method for estimating the quantity of silver. His general conclusion as to the correctness of the advice usually given to fix for twice as long as is required to "clear" the film is combated by the Editor of the “Photographic Journal of America," who found that thorough washing completely removed all the silver from plates taken from the fixing bath immediately all turbidity had disappeared.
           Weinhandler and Simpson patent a method of destroying thiosulphate and salts of weak sulphur acids by means of hypochlorite produced by the electrolysis of sodium chloride solution containing prints or negatives.
           Bainbridge recommends the permanganate test as the most delicate for thiosulphate, an indication being given by degradation of tint even at a dilution of 1 in 15,000,000; the mercurous nitrate test is more affected by common impurities and indicates only up to 1 in 2,000,000.
           A considerable amount of discussion has centred round the properties of various reducing solutions, a desideratum being a reducer having an effect proportional to the depth of image. Huse and Nietz, following up a suggestion of Deck, examined the effect of combined permanganate and persulphate, and also that of hypochlorite, both reducers being nearly proportional. Becher and Winterstein have examined the action of iodine both alone and combined with thiourea and with cyanide; they give also a general classification of the best known reducers. Greenal examined mixtures of thiosulphate and persulphate, which are much steadier in action than persulphate alone. Gear calls attention to the preserving action of potassium bromide, manna, and glucose on ferricyanide solutions. Smith recommends ammonio-copper sulphate in place of ferricyanide now that the latter is so expensive.
           A paper (by Crabtree" describes the variation of flash powders with their composition, both as to the metal and the oxidiser used, with the fineness of division of the metal and with the arrangement when fired. A mixture containing sodium oxalate, red phosphorus, a metallic powder such as magnesium or a mixture of magnesium and aluminium, and a substance such as strontium nitrate, is patented by him for the Eastman Kodak Co.
Wedekind has patented the use of metals such as zirconium, thorium, and titanium, mixed with their nitrates or chlorates for the production of smokeless and odourless flash-powders.
           Crowther has examined the chemical reactions involved in the chromium intensification process first suggested by Eder and afterwards modified and expanded by Piper and Carnegie in 1905. With Eder's original formula in which a higher proportion of acid is used than in any of the modifications suggested and which leads to only slight intensification, there does not appear to be any chromium compound attached to the bleached image. In the case of the other three formula given by Piper and Carnegie, where the intensification obtained increases as the proportion of acid is reduced, the amount of attached chromium also increases; in the extreme case this appears to be partly chromium hydroxide and partly chromium trioxide, the latter imparting a brown colour, and in the other cases only the hydroxide.

Positive Processes.

           The supply of platinum is still too limited for it to be available for photographic purposes. General Thayer is said to have discovered a considerable source of it in the Adirondacks, but that has not yet materialized. The Platinotype Company have introduced "Palladiotype" in which palladium is used to give effects very similar to those of platinum, and the use of palladium as a toning agent for collodion paper facilitated by a bath which contains ammonium chloride, sodium glycollate, and succinic acid and does not require a special fixing bath, has been recommended by Valenta. The latter has also investigated the properties of salts of diglycollatoferric acid from which an excellent blue printing paper can be obtained, but of poor keeping qualities. Valenta also draws attention to the fact that Sulzberger's patent on the use of ferrocyanide (mentioned in the last report) was forestalled by Fox Talbot in 1839 and that the process was mentioned in Eder's Handbuch.
           Strasser has worked out a toning method with the use of Schlippe's salt; Schering has improved his original selenium toning bath. Nietz and Huse have worked out in some detail the possibilities of obtaining sepia tones by the use of strongly restrained developers. Very few papers give good tones by this process; the best results are obtained by a chlore-quinol developer containing bromide and metabisulphite and necessitating an increase of exposure of from 75 to 100 times that required by normal developers.
Spitzer and Wilhelm have patented a combined toning and fixing bath containing tellurous or telluric acid or their salts along with thiosulphate.
           Two patents for transfer processes have been brought out, one by Pin for film in which coconut oil soap is the chief stripping agent, and one by Kent and Middleton for paper, using paraffin wax. A transferotype bromide paper on similar lines has been introduced by the Kodak Co.
           In process and allied work, Bull, Smith, and Turner have a paper on some of the intricacies of the half-tone process, Fishenden on the photographic engraving of rollers for intaglio printing, and Crabtree on the advantage of using citric and oxalic acids respectively in the preparation of zinc and aluminium plates for lithographs. Dorian has patented the use of a half-tone screen competed of small lenticular grains, preferably coloured (see also Knudson; Ann. Rep. 1. 303). Rieder obtains an intaglio printing surface by forming a screen surface in bichromated fish glue and getting a positive over that in caoutchouc and asphalt; Orans, for ease of correction, prints on emulsion coated on a serrated surface of the type of a Levy screen on celluloid or celluloid on glass.
           Meadway uses a mixture of naphthalene and a white metal, with rubber as adhesive, as costing for a projection screen, while Bebbington coats a support such as glass, gelatine, or waxed paper with a dull blue-coloured solution and projects on to that aide, the audience facing the other side.
           An interesting account is given by Warburg of the work of Meissling on the me of dyes such as erythrosine and auramine as hardening agents in the carbon and gum processes, an effect which is attributed to the formation of formalin. The erythrosin preparations are said to be quite equal to those containing bichromate and to have better keeping qualities.

B.V. STORR, M.Sc.