1902| MICROSCOPICAL J OURNAL 23 
brass stage with wheel diaphragm, but with graduated 
draw-tube, spiral rack-and-pinion coarse adjustment, mi- 
crometer screw fine adjustment, and double mirror, for 
the sum of $13, complete in mahogany case. 
BavscH AND LomB MicroTomMEs.— Messrs. the Bausch 
and Lomb Optical Company have recently issued a new 
catalogue of microtomes, and have submitted to our no- 
tice several of the instrments listed therein. The most 
important of these are the Minot Automatic Rotary and 
Minot Automatic Precision Microtomes, of elaborate con- 
struction, and consequent high price, which are more es- 
pecially designed for advanced work. The laboratory 
microtomes of this firm are of equal excellence of design 
and workmanship, if somewhat less elaborate in form. 
In these the object to be cut is raised by a screw with a 
feed adjustable from two to sixty micra, the adjustments 
being so arranged that any desired cutting angle or length 
of stroke can be had. The knife itself is carried on a v- 
shaped block. A microtome of this description, with feed | 
operated by :hand-lens, is listed at $50, complete with 
knife and holder. A smaller microtome is ofa similar 
design, but the object is raised by a micrometer screw 
with a pitch of 5 mm., with a graduated head divided 
into a hundred parts; so that each graduation has, there- 
fore, a value of 5 micra, and there is no automatic feed. 
This microtome is specially designed for students, and 
costs, with knife and holder, only $24. A very sub- 
stantial table microtome, somewhat of the Leitz type, 
costs $13. Amongst new designs may be mentioned a 
simple microtome for freezing with carbon dioxide gas, 
which can be attached to the gas cylinder. 
Mountine WEB oF SpiIpER.—I found no difficulty in 
mounting spiders’ webs in balsam. I painted a strip of 
varnish across the two ends of a clean slide,and held this 
flat against the web; the slide was covered with it, and 
