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THE BRITISH JOURNAL OF PHOTOGRAPHY. November 1, 1860, p.310

OBSERVATIONS ON ALBUMENISED PAPER AND ALKALINE GOLD TONING.
No. III.

BY C. JABEZ HUGHES.

ALBUMENISED PAPER.--Photographers are not agreed whether the, best albumenised paper is that which has the highest gloss. The majority certainly run after the glitter; but the old proverb holds good again, for the most perfect paper cannot be made to take the same high glaze that some inferior ones do. This rage for gloss has a great tendency to drive albumenisers to adopt some of those tricks they have recently been charged with--of using gelatine, stale: eggs, and other objectionable means to produce this strong glaze. Admitting that albumen-brilliancy is desirable, its production should only be by legitimate means. An intensely high glaze is not the only thing needful in an albumenised paper. This fact cannot be too strongly insisted on; and photographers must be made aware that albumenisers cannot give any glaze they please indifferently on all papers, and that some very good papers, though taking a very high surface, will not compete m that respect with the commoner and, in other respects, inferior French papers.

Albumenising paper is an operation requiring great care and knack. In consulting with several who do it on a large commercial scale, I find they have few or no secrets. Their, success lies in that careful manipulation acquired only by considerable practice and experience. For the supply of eggs they depend on the egg merchants; though I know one party who uses only fresh-laid eggs, and he charges many of the defects of the common albumen to the foreign eggs being packed in lime, which, permeating the porous shell, acts on and inures the albumen, the presence of the lime, according to the statement, being evident in the taste of the albumen. The quantity of eggs consumed in preparing photographic paper must be very great. In one establishment I recently saw a box containing 1100. I was assured that two of these were used every week. This would give upwards of 114,000 per annum used by this person alone!

When the highest glaze is wanted it is the practice to add no water whatever to the albumen: the crystals of chloride of ammonium or sodium are added and beaten up with it, and thus made to dissolve. When it is in the condition to be used--some use it when a day old; and reject it at the end of a week; some begin to use it only when it is a week old--it is placed in dishes larger than the whole sheet of paper: the sheets are carefully floated, and then hung up to dry in a warm place. The rooms where the albumenising is conducted are kept at a high temperature, it being a most important circumstance to dry the sheet as quickly as possible after taking it from the albumen.

Chlorides of sodium and ammonium are each used, and it is believed that there is not much difference. On plain paper the nature of the chloride is of consequence in affecting the tone; but with albumenised paper it is thought that this effect is practically ignored by the influence of the large amount of albumen. Chloride of barium I do not find in general use.

There is a considerable agreement about the quantity of salt to be used. From ten to twelve and a-half grains per ounce is considered the proper quantity. One party, however, uses fifteen grains. The sixty-grain silver solution will therefore be about the strength required for nearly all papers.

For those who wish to albumenise their own paper, the operation is as follows:--Obtain as many eggs as are required ounces of solution to fill the dish to the depth of half an inch. Break the eggs individually in a cup, being careful not to disturb the yolk; then extract the germ, and pour the albumen in a large vessel to be used for beating it up. By treating each egg alone, any one which may have the yolk broken, or that is not good, can easily be rejected;, for one bad egg may spoil the whole batch. Next add chloride of ammonium, ten grains for each egg. Dissolve the chloride in as little water as it will take up, and add it to the albumen: beat the latter till it all becomes a stiff froth, and not a drop of fluid remains. Allow it to remain for twenty-four hours, then pour it through a fine muslin into a shallow dish. Float the paper carefully on the albumen so as to avoid air bubbles: this is the most delicate operation, and great knack is required to do it properly; for if an air-bubble once occurs, although it may be removed, it will always show in printing, therefore the sheet must be so laid down that none be formed. The length of time the sheet must remain on the albumen depends on the kind of paper. Generally it is from sixty seconds to two minutes. If the paper remain too long the albumen sinks deeply, and the surface dries dull. In lifting the sheet off' as much skill is required as in laying it on. It must be lifted with one steady regular motion, any hesitation or stopping causing a streak or series of streaks. The sheet must be suspended by two corners, so that it may drain and dry in a uniform manner. When the albumen is set the sheet may be dried by the fire: the quicker it is dried the greater the glaze. When dry the operation is, strictly speaking, finished, and the paper. ready to be silvered for printing; but, as usually prepared for commerce, it passes through another operation--that of pressing.

Formerly it was thought necessary to smooth the paper with a hot iron to coagulate the albumen prior to sensitising, and as this was inconvenient on a large scale, it was sent to the hot-presser's Though it has since been discovered that the silver solution itself sufficiently coagulates the albumen yet the pressing--now cold pressing--remains.

This process the albumenisers cannot manage themselves, but send the paper to the card glazers', who, for a small charge, do it for them. The, operation is simple. Two highly-polished steel plates, kept expressly for this work, are provided, and two sheets of albumenised paper, back to back, and albumenised surfaces to the steel plates, are placed between them. They are then put under heavy rollers and, submitted to powerful pressure. This takes out the curl the paper gets from albumenising, and causes it to lie flat. It also communicates a peculiar gloss and apparent fineness of surface, which is, however, purely artificial, and disappears when wetted; and it is worth while considering whether photographic paper should pass through this operation. It is a question of advantage and disadvantage. By the process of pressing the paper loses its curl, acquires a delusively fine face, and lies invitingly smooth in a tradesman's drawer; but for practical end, "its sole and only recommendation is, that it lies more easily on the silver solution.

The disadvantage of the pressing is, that the paper passes from those who understand it and are interested in keeping it clean and perfect, into the charge of careless boys, who handle it with dirty hands; that particles of dust and dirt that adhere even to polished steel plates are ground into the surface; and that; often the albumen itself is much injured in the rolling, sometimes literally crushed, to the entire prevention of getting a good print, through too much pressure being used. Is it desirable, for so small an advantage, that so much risk should be run ? I think not. Some persons who prepare a great deal of paper have set their faces against it, and will not have their paper rolled. Others laughingly say, "the public like it--are tickled with a shining face; that high glaze, like charity, covers a multitude of sins; that though it is little else than a sham, let them have it who know no better." The grain and structure of a paper is very much opened up in albumenising, so that its nature can be judged; but, if it be pressed, an apparent fineness is communicated that cannot be relied on, and one means of forming an estimate is removed. Nearly all the finger marks--how frequently a fine and unnecessarily perfect representation of the whole five digits!--are attributable to handling with dirty hands during the pressing operation.

I strongly recommend photographers to discontinue the use of rolled or pressed paper.

When the printing is all over, and the picture mounted on card. board, then is the time to press it, and take full advantage of the fine surface to be communicated.

Is gelatine used by albumenisers to give increased glaze .to their papers? The assertion is frequently made, and there may be truth in it; but, from inquiries I have instituted in very many quarters, I can get no evidence of it.. The nearest approach is the practice, said to be adopted by one party, of sponging his sheets of paper, first with a, weak solution of gelatine, then having them pressed, next albumenising, and finally pressing again; .but this operation is only equivalent to giving the paper an extra sizing to create a harder surface, so that the albumen, by being more superficial, will give greater glaze. Those who adopt adulterations generally do it for cheapness; but any paper passing through a, double operation of this nature must be enhanced in price.

I have certainly met with papers, albumenised in France and sent to this country, that have had a very suspicious odour; but I think the practice of all respectable parties in this country is to use albumen only. Albumen is, however, used in different states. When newly prepared it does not give such high glaze as when it is older. If albumen prepared yesterday be used to-day, it will not give much glaze--it sinks into the paper: to-morrow it will do better: in three or four days time it will .be in first-rate order. This, however, depends on temperature and period of the year. One of the troubles of the albumeniser is the keeping his albumen in order, and when it is in its best condition, to use it up as rapidly as possible. Some persons keep their albumen for a fortnight or more before they use it-the object being to concentrate it, to evaporate the water from it, and make it thick; and in this state it will give a very high glaze upon even a porous paper. But this is certainly pushing things too far, and the paper will show it; for instead of being white it will be decidedly yellow, from the thick layer of decomposed albumen. When paper prepared in this manner is moist, both the colour and adhesiveness of


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