MICROSCOPY. ; 127 
on two parallelograms of metal, the outside of A carrying lips C ` 
and D, the latter provided with a thumbscrew by which it can be 
fastened to a table. The front ends of A and B in the drawing 
are cut off to show the arrangement of the rods E and F that 
are firmly inserted in A, but permit B to slide freely on them. 
They are threaded on the outer ends and have thumbscrews by 
which B can be pressed to A; the thumbscrew on F not shown. 
H is a sleeve on F forming Fig. 45. 
one end of the curved lever 
_ G, that has a motion regu- l 
lated by the screw J hanging 
from the rod E. 
To use the instrument some 
narrow pieces must be pro- 
vided equal in length to the 
depth of the- instrument. 
These pieces I call blanks, 
and they may be of rubber, 
paper, or wood, slightly thick- 
er than the “stem to be cut, 
which stem should not be 3 : 
more than half as long. A follower is also required as large as the 
stem and so long that with the stem it will reach from the guiding 
surfaces to the lever @, when the latter is pressed down as far as 
I permits. Laying the instrament on its side remove B, lay the 
stem on A, at any desired angle to the guide, bring a blank up to 
it on either side, insert the follower, replace B, screwing it up 
tight, and by the screw J, which should be very fine, the lever G 
forces the follower and stem above the guides as in the old instru- 
‘ments. For animal tissues, they are bedded in soap in little paper 
_ boxes, and when cold the mass is treated as astem. A vessel 
with an inner lip to hold the microtgme, and screw working 
through the bottom, makes jt refrigerating. Longitudinal sections 
Sof wood are beautifully cut, by clasping one end a little tighter. 
Be than the other, against which the follower works, the section thus 
commencing at nothing. Of course a variety of followers and 
blanks can easily be provided to suit various cases, and a little 
- Manual tact is required; but in my hands I find it takes less time 
for manipulation than any other instrument, with a range of work 
=- before impossible. — Wm. H. SEAMAN, Howard University. 
My 
Shiai 
