310 PHOTOGRAPHIC FACTS AND FORMULAS 
loid, and without shifting the celluloid the registration pins 
driven through it. Then the celluloid should be laid on the 
second colour print, the sketched-in outlines made to coincide 
and the pins driven through the print. The third print is 
treated in the same way. 
Another simple method was suggested by Bohm, as shown 
in Fig. 9, in which a is a sheet of plate glass on which is 
Fig. 9 
placed a sheet of fluffless, smooth blotting paper, then on this 
the freshly inked bromoil b, and then a sheet of smooth, hard 
drawing paper c. The latter is preferably fastened at one 
end to the glass plate so as to prevent it shifting. As a roller 
a knitting needle of one-eighth inch diameter is used, which 
can be seen as the little round circle between the boards. 
Pressure is obtained by means of the top board. The transfer 
can be examined after it has been rolled, and if unsatisfactory 
can be rolled again in the same direction. For prints larger 
than 5 x 7 it is preferable to use a rather more elaborate 
arrangement, shown in Fig. 10. This acts well up to 16 x 20. 
Fig. 10 
On each of its longer sides a U-shaped iron strip is fastened 
by two or three screws; the holes must be about two-fifths 
