The Photographic News. Vol. 10, No. 41. August 17, 1866. p.395
DEAR SIR,--The letter of your correspondent, "P.J.K.," in last week's number, induces me at once to carry out an intention I have for some time entertained to ask your assistance in finding a remedy for certain yellow stains which have troubled me for some time past, and which appear to me to be of the same character as those above mentioned. The first time I noticed this defect was about a year ago--I think in July--and I have several times had to reject as useless thirty out of one hundred prints. I then thought, like your correspondent, that the fault lay in the paper, and I changed the sample for that of another maker, with great benefit to the colour and goodness of the prints, but with no effect as to the evil in question; and subsequent experiments have shown me that five or six or more would be bad out of a sheet, and the rest as good as need be, and these, too, from different parts of the sheet. I therefore dismissed the paper as a cause. I have very carefully noticed all the different stages of the operation, and am not now able to say where the stains are made; and I shall feel greatly obliged to you or any of your numerous readers who can point out a remedy. To make the matter clear, I think I should detail my mode of proceeding, which is this:--I float my paper for two minutes on a bath of 100 grains to the ounce, and drain and dry usually from 120 to 170 cartes for a batch; I print all, and place them from time to time, as done, in a Marion's case. I then float for a few minutes on a shallow bath of water to remove as much as possible of the free nitrate for precipitation and recovery; wash through a tray of water into a tank lined with gutta-percha, where, with frequent changes of water, a number are accumulated, and then, from time to time, removed to another vessel of earthenware, till the whole are washed, when I proceed to tone them, using the carbonate of soda bath, as I detailed to you some two or three years back, washing through till all are toned, and washing again with several changes of water. I then fix in fresh hyposulphite solution at 1 to 6, allowing one ounce of the salt to each sheet of paper. That the evil does not arise in the printing bath I am quite certain, as I perceive it before the prints are put in, and if it is only a slight case, the hypo removes it; that it takes place in one of the two washings, either before or after toning, I feel certain, but I cannot say which, though I incline to the belief that it is in that before. I enclose some specimens, by which you will see, on the backs especially, markings as though one print stained that next to it. I should add that the stains never appear in small batches of prints--say forty to sixty--as in cold weather.
I have to apologise for the length of my letter, but I did not feel I could put the matter fairly before you with less detail to have a due regard to perspicuity.--I am, dear sir,
yours very sincerely, FARINDON LANE.
Rotherham August 10th, 1866.
P.S.--I have often noticed the turbidity of the developer on adding methylated spirit, which I only do, when compelled, in the small quantity in the developing glass. I have also noticed flocks of pinholes occurring in large numbers at times, and then ceasing altogether; but I never thought of associating the two as cause and effect, which doubtless they are. I shall certainly avoid methylated spirit for that use in future.
[We shall be glad to receive hints or details of experience on the subject of spots in albumenised prints, which are frequently so perplexing.]