82 
I prefer to develope with an iron solution, using only suffi- 
cient to cover the plate ; and with this developer and collodion, 
when the plate has been properly exposed, a negative can be 
obtained which will not require intensifying afterwards. Not 
having had sufficient experience with pyrogallic acid I cannot 
speak with confidence as to any advantage it may possess in 
giving fine texture to the negative. With the bath and 
collodion exactly in the proper state, there is no doubt that 
with this acid negatives may be had as quickly as with iron ; 
but it is extremely difficult to have everything constantly in 
the best working order. Unless the greatest attention be 
given to this matter, the time of exposure is so much increased 
that iron, for this reason, must have the preference. 
Upon the character of the image after development entirely 
depends the value of the enlargement to be made from it, and 
in this direction there is much room for improvement. Even 
in the best negatives }et made defects from this cause are very 
apparent. The microscopic photographs by Mr. Dancer have 
the finest texture, and will consequently bear greater magnify- 
ing than any other photographs I have ever seen, hut the 
process by which they are made is not published. 
The weather in this conn try is so very uncert'ain, and suc- 
cess in this branch of photography is so entirely dependent 
on the state of the atmosphere, that it is necessary to be 
always prepared to take advantage of a favourable night. I 
have a small cupboard placed in a convenient part of my 
house where there is a supply of water, and the temperature 
is always much above the air outside. This cupboard is just 
large enough to hold a small glass bath fixed at the proper 
angle ready for use, also the bottles for collodion, bath, 
developing and fixing solutions, and other little requisites. 
This arrangement is so convenient that when there is a pros- 
pect of getting a negative I can set the telescope, prepare the 
plate, and take a negative in less than ten minutes. But 
when there is a chance of two or three hours’ work an 
assistant is desirable, as the best results can only be obtained 
