Microscopy. 945 
MICROSCOPY.: 
Mrnor’s AUTOMATIC MICROTOME.—The principle of this Micro- 
tome is to obtain sections by moving the object to be cut in a ver- 
tical plane past the knife which is held in a fixed position. The 
knife is clamped by two screws in jaws at the top of two upright 
pillars to be seen in the figure. The object to be cut is imbedd 
in paraffine and stuck on to a circular brass plate which faces the 
knife, when the plate is in position. This plate has the motion in 
three directions, and may be revolved around its own centre, so that 
the position of the object may be adjusted as desired. The well- 
known construction, used on the Schanze Machines, has been 
adopted to secure the necessary play of movement for the plate, 
carrying the paraffine. This construction was selected on account 
of its simplicity and convenience, and the great firmness with which 
the plate may be clamped. The object holder rests on a horizontal 
plate which may be fed towards the knife by a micrometer screw, 
the head of which is a toothed wheel. Hach tooth equals ybg mm. 
forward movement. The whole of this complete object-carrier is 
fastened to an upright slide. The slide is worked up and down by 
a crank, as seen in the cut, and the crank is moved by turning a 
heavy iron wheel. 
1 Edited by C. O. Whitman, Director of the Lake Laboratory, Mil- 
Waukee, Wis. 
