PHOTO-MICROGRAPHIC APPARATUS. 
37 
was admirably carried into effect by the notable 
excellence of the workmanship; moreover, the details 
are, to a great extent, due to the experience and 
ingenuity of Messrs. Swift. 1 he trestle alread} 
mentioned, as supporting the ocular end of the 
tube, will be noticed, and the other characteristics 
of strength, and of length of body, are seen at 
a glance. The arrangement for effecting the fine ad¬ 
justment motion is intricate, and as it was, later, 
altered, it need not be described here. A large 
T-headed screw, under the body, however, requires 
notice, as it is an essential part of an arrangement 
which we put forward as important for convenience of 
working under ordinary conditions, though we do not 
say it is a necessity, and though it is not used by some 
of our best workers. The microscope and the illumin¬ 
ating apparatus are mounted on a turntable, which 
revolves on the pivot formed by the large screw under 
discussion; so that the operator may stand or sit at 
one side of the entire apparatus, turn the microscope 
and light out from the central line, apply his eye 
directly to the ocular, and arrange the lighting, centring 
tube or collar-correction, etc., and then return the 
microscope and light to the normal or axial position. 
This is infinitely easier and handier than putting 
the head in between the microscope and the front of 
the camera, not to mention arranging the object on the 
microscope wholly detached from the apparatus, and 
then setting the microscope in position. The back of 
this camera is fitted with sliding parts so that the slide 
