_Photographic Notes_ (Vol. vii., p. 363.).--I wish to correct an error
in my communication in "N. & Q." of April 9: in speaking of "a more
_even_ film," I meant a film more _evenly sensitive_. I am sorry I have
misled MR. SHADBOLT as to my meaning. I have very rarely any "spottings"
in my pictures; but I always drop the plates once or twice into the
bath, after the two minutes' immersion, to wash off any loose particles.
I also drain off all I can of the nitrate of silver solution before
placing the glass in the camera, and for three reasons:--1. Because it
saves material; 2. Because the lower part of dark frame is kept free
from liquid; 3. Because a "flowing sheet" of liquid must interfere
somewhat with the passage of light to the film, and consequently with
the sharpness of the picture. I think it is clear, from MR. SHADBOLT'S
directions to MR. MERITT, that it is no very easy thing to cement a
glass bath with marine glue.