THE MICROSCOPE. 
Vou. VI. ANN ARBOR, MARCH, 1886. No. 3. 
ORIGINAL COMMUNICATIONS. 
HOW TO MAKE PHOTO-MICROGRAPHS. 
THIRD PAPER. 
W. H. WALMSLEY. 
We now come to the form of Camera devised by myself, 
and which is in daily successful use by many of our leading 
workers throughout the country. The instrument in its present 
form is simple, compact, and most perfectly adapted to every 
description of Photo-Micrographic work, with high or low pow- 
ers. It is substantially constructed of mahogany; the body 
being square, and carrying a single dry plate holder, which per- 
mits the use of plates 44 x 53 or 3} x 44, vertically or horizon- 
tally, as may be necessary. The focusing screen, (of finest 
ground glass,) is hinged at the bottom, and held in position on 
top, by means of a spring catch, which also secures the plate- 
holder in place. To the centre of the screen a circular dise of 
thin microscopic covering glass is attached by means of Canada 
Balsam, the use of which will be explained further on. The 
front of the camera is removable, and carries either a board 
to which a lens may be secured for ordinary photographic pur- 
poses, copying, etc.; or a short cone to receive the tube of the 
microscope. The bellows are in two sections, with a centre 
division of mahogany, and a total extension of two feet; which 
is sufficient to give a range of magnification from 100 diameters 
to 230, with a one-fifth inch objective; and a corresponding range 
with any other power. The bellows slide smoothly upon V 
shaped ways, and are secured at any desired point, by means of 
a cam, operated by a lever, convenient to the hand. For greater 
portability, and also for convenience when using powers requir- 
ing only a short extension of the bellows, the frame upon which 
