VARNISHES | 1s) 
may be used either as a hot or cold varnish, and takes the 
retouching pencil well. 
MatTr VARNISHES.—These are generally used on the backs 
of negatives either to hold back certain parts in printing, or 
to facilitate working up with pencil or crayon: 
Gum sandarac, powdered 53 g 400 gr. 
Gum dammar l6g 120 gr. 
Ether 700 ccm 11% oz. 
Allow to stand with frequent shaking until dissolved, then 
filter, and add: 
Benzol 300 ccm 434 oz. 
and: 
Alcohol lto5ccm 7to 35 min. 
The quantity of alcohol determines to some extent the fine- 
ness of the matt grain. The following may also be used: 
Gum sandarac, powdered 722 504 gr. 
Ether 715 ccm 114 oz. 
Shake until dissolved, filter, and add: 
Toluol 285 ccm 44 oz. 
This does not give such fine grain as the former. 
For celluloid negatives the above varnishes with alcohol- 
ether solvents are not suitable, as the latter attacks the base. 
The following is suitable: 
Amber 25, 192 gr. 
Benzol 1000 ccm 16 oz. 
The amber should be added in fine pieces, and the mixture 
digested in a warm place for two or three days, with occa- 
sional shaking, until the resin dissolves, then filter. 
There is frequently trouble when making varnishes, from 
the gums and resins compacting into a solid mass at the bot- 
tom of the bottle. This may be avoided to a great extent by 
using a wide-mouth bottle and suspending the resins in a 
little bag of fine muslin at the top of the liquid. As the resins 
