Read at a meeting of the South London Photographic Society, April 9th, 1863

THE finding of a substitute for albumen for positive printing has for a long time more or less claimed the attention of photographers; but I do not think that sufficient perseverance has been shown in the pursuit. Many, I dare say, have tried an experiment or two, met with no good results, and fallen back upon albumen, leaving the trouble of finding a substitute to others possessed of more patience than themselves. Only those who have gone on with their experiments can know the difficulties that spring up at every point. They are that it requires many a glance at the golden end in view to keep the enthusiast from giving up in despair.

The subject of printing has at no time received the attention it deserves. Negatives can now be produced nearly, if not quite, perfect; and it seems to me very strange that more care has not been shown in that process by which their beauties are exhibited to the world.

As has been recently remarked, every photographer ought in order to produce the best result, to have the printing of his negatives under his own supervision. But, yet, when perfect prints are produced, the chances are that they are not permanent, and in a few years, or even months, their beauties begin to fade; so that if it be the portrait of a handsome young lady, the likeness, keeps pace with the original. It is a most essential point that photographs should be as permanent as engravings.

Photography is a great blessing; for, by its means, we may possess faithful records of places and events of the greatest national or private interest, and of the features of those far distant, or who have passed away from among us to that "bourne whence no traveller returns." But what is more grievous than to see the cherished likeness of a lost one gradually fading way, when we had hoped to hand the semblance of those loved features down to generations yet to come!

There are some remarks of Washington Irving's, on the introduction of the printing-press, which apply with such force to photography that I am sure you will pardon me for quoting them in a paper which professes to dwell upon processes and formulae He says:

"The recent invention of the art of printing enables men to communicate rapidly and extensively their ideas and discoveries. It brought forth learning from libraries and convents, and brought it familiarly to the reading desk of the student. Volumes of Information which had before existed only in costly manuscripts, carefully treasured up and kept out of the reach of the indigent scholar acrd obscure artist, were now in every hand.

"There was, henceforth, to be no retrogression in knowledge, nor any pause in its career. Every step in advance was immediately, and simultaneously, and widely promulgated recorded in a thousand forms and fixed for ever." There could never again be a, dark age. Nations might slut their eyes to the light, and sit in wilful darkness, but they could not trample it out: it would still shine on, dispensed to happier parts of the world by the diffusive powers of the press."

In what a greater degree does not photography accomplish all these blessings!

I have; made the foregoing remarks to impress upon you the importance of the subject--"The Improvement of Formula; for Photographic Printing."

We must make our prints more; permanent; and, as it is exceedingly dangerous to employ albumen for printing processes, I, as you are aware, am a great advocate for its removal altogether from our formulae.

I will briefly call your attention to the only advantages possessed by albumen. It gives great fineness of definition, combined with a high degree of transparency, and depth in the shadows (which last, allow me to observe, is not always according to nature. I think I shall be supported in this idea by many). These two good qualities are set against a long; array of serious defects:

1. The trouble and vexatious failures in manipulation,

2. The great; uncertainty of the result to be obtained,--two sheets of albumenised paper very seldom being alike.

3. Its. proneness to mealiness and what I term scarlet fever, viz., large patches being left unacted upon by the toning bath. This is really a species of mealiness.

4. Its great liability to become yellow by sulphurisation, and thereby fading of the image.

5. Its great gloss of surface, which is very inartistic.

There are many other faults to be found with poor Albumen which I need not enumerate. I shall now make a few remarks on the processes that appears to me to stand any chance of beating albumen out of the field. The processes in question are--the resinised paper, paper prepared with India-rubber, and the new enamel paper, introduced by M. Schering or Herr Liesegang, or by both of these gentlemen.

On the subject of resinised paper I have not much to say, as I have made no alteration in the formula, except in the bath, which I now use of the strength of at least 100 grains to the ounce (more commonly 120 grains); and I only float the paper from two to three minutes. The bath should also contain five to ten per cent. of alcohol, as I recommended in the first instance, or sometimes the paper will be found to repel the solution, causing a most disastrous effect..

[Mr. Cooper here exhibited a piece of paper that Mr. Simpson had received from a correspondent, in which one-half was quite insensitive to light, and it appeared as if a solution of nitrate of silver had been carelessly brushed over without forming any chloride in parts.]

The only other point is to wash the prints finally in boiling water. From the India-rubber paper I expected much better results than I have as yet obtained. It decidedly gives cleaner lights and as good shadows as resinised paper. The following is the modus operandi of preparing it. Procure some pure India-rubber or gutta-percha (that sold in thin sheets is the best), dissolve it in a little chloroform, and add it to benzole in the proportion of from two to three grains to the ounce; shake it well, and immerse the bottle containing it in hot water till the solution is bright and free from muddiness. Allow it to settle for some time to prevent white spots from being visible on the finished prints. To prepare the paper, pour some of the solution into an even-bottomed dish, and immerse the paper in the way I described for resinising paper. The draining is the most important part of the process, and where a failure is most likely to occur. The paper must be so hung that one corner is lower than the other, and just before it ceases to drip the position of the sheet should be reversed, so that the solution may drain from the other bottom corner. A difficulty is to get a suitable sample of benzole, as it is generally very liable to run into greasy streaks. If it has originally the least tendency this way, it will only be increased by the addition of the India-rubber or gutta-percha. When the paper is thoroughly dry it may be floated on a solution of any of the chlorides of from five to ten grains to the ounce. A little Iceland moss may be added to the salting solution with advantage. Float three minutes on a nitrate of silver bath of sixty grains to the ounce of water, slightly acid. Or a combination of the nitrate of silver and ammonia may be used, formed as follows;--

Make a solution of ammonio-nitrate of silver, 100 grains to the ounce of water and add nitric acid till the solution is neutral or faintly acid. By-the-bye, plain ammonio-nitrate of silver answers very well for this paper. The toning, fixing, and washing are performed as usual.

We now come to the consideration of the enamelled paper. Of this I have great hopes, and think I shall soon be able to employ it successfully for cartes and the finest work. I have not yet made many experiments with it, as I only. had a piece of the size of a carte de visite for which I was indebted to Mr. Simpson. I have since received some from Glasgow, so I trust by our next meeting to have some perfect prints on it to show you. As the piece of paper I received was albumenised (of course, for my purpose), it was necessary to remove the albumen. I accomplished this by floating on repeated changes of distilled water (the object of my using distilled in preference to common water you will perceive presently), and gently dabbing the surface with a clean sponge. To make sure that I had entirely got rid of the albumen, I floated a small piece of the paper on the nitrate bath (I beg your pardon: nitrate of silver bath I should have said). I then exposed it to strong sunlight for the whole of the day, when not the least change took place in the print; except at the edges, where the silver solution had come in contact with the unprotected paper. This also, proves that the enamel is unacted upon by the nitrate of silver. If I had used common water a, slight difference might have been made in the result. This was to me a most satisfactory experiment.

I have brought a piece of the paper from which the albumen has been removed. You will perceive that the surface is very nice, although it has a slightly bronzed appearance. To salt the paper, I floated it for two minutes on a seven-grain-to-the-ounce. solution of pure chloride of sodium and their, when dry, on the 100-grain-to-the-ounce-of-water nitrate of silver bath.

One advantage is that the paper does not cockle in drying. The piece I tried printed very red in the pressure-frame, but toned up beautifully to a splendid purple. Upon fixing the print lost considerably in tone, but not in strength; but when dried it was very much too blue. I must try and procure some of the paper unalbumenised, and then 1 can set to work in a systematic manner.

I forgot to mention drat the enamel is insoluble in hot and cold water and alcohol. It is also unacted upon by nitric, hydrochloric, and acetic acids, diluted with their volume of water. I have tried many experiments to make an enamelled paper, but have not as yet been successful.

This paper is necessarily a very cursory one, as through severe cold I have been prevented from carrying out a great number of experiments which I have in hand. In fact, I was rather inclined to postpone my promised communication till the next meeting, as I thought we should have plenty for the evening; but, as Mr. Harmer was prevented from fulfilling his intentions, I have done the best I can to open the way for a discussion on this most important subject.