134 
PRACTICAL PHOTO-MICROGRAPHY. 
Alum ... 
Water ... 
•J ounce. 
20 ounces. 
Wash for five minutes in running water. 
Toning Solution. 
A. Sodium acetate ... 
Water... 
Gold chloride one tube of 
600 grains. 
20 ounces. 
15 grains. 
50 grains 
20 ounces. 
B. Ammonium sulphocyanide 
Water... 
Take of A 1 part, B 1 part, water 2 parts. Keep for 
an hour before use, or put into the solution some scraps 
of printed “ Solio,” when toning may be begun at once. 
Keep the prints apart from each other and in constant 
motion, and when they have the desired tone, wash 
well and fix in : 
Hyposulphite of soda ... ... 3 ounces. 
Water ... ... ... ... 20 ounces. 
For at least fifteen minutes. Then wash very carefully 
in running or frequently changed water. 
Washing may be accelerated by laying the prints 
face down on a slab of glass or ebonite, and passing 
repeatedly over their back a “squeegee,” while the water 
from a rose tap is playing on them ; this should never 
be omitted. After this treatment the prints will be 
washed by an hour’s sojourn in running water. If 
allowed to dry naturally, the prints will have a fairly 
glossy surface ; if a high gloss is desired—and for our 
work it is often most valuable—they should be squeegeed 
down gently to a glass or “ferrotype ” plate, previously 
cleaned and polished with a little “ French chalk.” 
The method of procedure is as follows: Lay the plate 
face upwards in a dish of clean water, the print face 
