308 PHOTOGRAPHIC FACTS AND FORMULAS 
just around these holes, painted with celluloid varnish. This 
is to prevent the absorption of water around the holes, so that 
they will not be deformed and thus cause non-registration 
in subsequent printings. 
Any paper may be used to transfer to, but the soft copper- 
plate or collotype papers are the best, as they absorb the ink 
slightly and give a more velvety appearance. It is important 
that the paper be lightly sized, otherwise the surface may 
tear in patches. A good size can be made by boiling 2 per 
cent of starch in water, and this can be painted over the 
surface with a flat brush. Too much size prevents transfer. 
Hard, thick papers may be soaked in water and placed be- 
tween thick fluffless blotters under light pressure for a little 
time to even the dampness. 
Fig. 7 shows the laying of the transfer paper on the marked 
Fig. 7 
bromoil and the method of fitting the pins. A, B in Fig. 7 
show the correct way to hold the tool and C the correct angle 
for this. The strokes may be either elongated ovals as in A, 
