The plate must be left in this bath until the zinc solution has thoroughly penetrated the film (we have found five minutes amply sufficient for this purpose, although a much longer time is of no consequence); it should then be taken out, allowed to drain upright on blotting-paper until all the surface moisture has been absorbed (about half an hour), and then put by until required. The nitrate of zinc, which is still retained on the plate, is sufficient to keep it moist for any length of time, and we see no theoretical or practical reason why its sensitiveness should not be retained as long: experiments on this point are in progress; at present, however, we have only subjected them to the trial of about a week, although at the end of that period they were hardly deteriorated in any appreciable degree. It is not necessary that the exposure in the camera should be immediately followed by the development, as this latter process can be deferred to any convenient opportunity, provided it be within the week. Previous to development, the plate should be allowed to remain for a few seconds in the original thirty-grain silver-bath, then removed and developed with either pyrogallic acid or a protosalt of iron, and afterwards fixed, &c. in the usual manner." * * * * * Replies to Minor Queries. _Tippet_ (Vol. ix., p. 370.).--P. C. S. S. cannot help thinking that _tippet_ is nothing more than a corruption, _per metathesia_, of _epitogium_. Such, at least, seems to have been the opinion of old Minsheu, who, in his _Guide to the Tongues_, 1627, describes it thus: "A habit which universitie men and clergiemen weare over their gownes. L. _Epitogium_, ab [Greek: epi] and _toga_." P. C. S. S.