_A Query respecting Collodion._--I have been making some collodion by Mr. Tery's process, and have iodized it with a very sensitive medium. The collodion is very clear and properly diluted. The ether I used had a very powerful smell of sulphur, and was likewise very strong and volatile. I diluted it with an equal {526} volume of alcohol. The ether was then still very strong. The cotton dissolved freely. On mixing the iodizing medium, the colour of the collodion turns immediately to nearly a port-wine colour, but still remains very clear. I obtain a very good film of iodide of silver from the bath, but cannot produce a picture under five or seven minutes, whereas with the same lens, and the same iodizing medium, viz. Alcohol 8 drms. Iodide of potassium 8 grs. Iodide of ammonium 4 grs. Iodide of silver ½ gr. I have obtained beautiful pictures in less than one second with collodion prepared by the same (Archer's) process. As I have made a quantity of it, and am unwilling it should be wasted, I have taken the liberty of asking your opinion on the subject. Do you think the collodion is too new, or the ether not good? On pouring the developing solution on the plate (protosulphate of iron), the plate has the appearance of having ink poured on it; but this appearance is removed on the application of the hyposulphite of soda, and the plate remains as clear as when it was taken from the nitrate of silver bath. J. COOK. _The Céroléine Process._--Have any of your photographic correspondents made such experiments on the céroléine process as to enable them to communicate the results to "N. & Q."? Is Mr. Crooke's process for preserving the sensitiveness of collodion applicable to all collodions? If not, what collodion is best suited for it? SILEX. _Mr. Fox Talbot's Patents._---The injunction moved for by Mr. Fox Talbot, as reported in _The Times_ of Saturday last, reminds us of a Query which we have been sometimes asked, and which may just now be brought forward with advantage, namely: If Mr. Talbot's patents extend to the collodion process, how comes it that the earliest practisers of the collodion art had to make their own researches? We know one skilful photographer whose experiments were so extensive before he made any tolerable pictures, that his spoiled glass and cuttings were more than a man could lift. * * * * * Replies to Minor Queries.