28 Microscopy at the American Exhilition. By R. H. Ward. 
facility and in an easily measured position around the object as a 
centre. He also exhibits a new pocket microscope of neat and 
apparently serviceable construction. 
T. H. McAllister’s case, in the photographic building, exhibits 
his two or three grades of instruments, with chain movements, thin 
stages, and often iron bases, built with a view to both economy and 
excellence ; and also a new-model physician’s microscope, which is 
literally a charming little instrument, very portable and handsome, 
and combining with most of the excellences of the maker's former 
work the Zentmayer glass sliding stage and the diaphragm in the 
stage close to the object. The objectives furnished with it vary 
from fair to the best, according to the pecuniary views of the pur- 
chaser. The accessories are of the usual forms. 
Bausch and Lomb, of Rochester, who have lately added to the 
province of the Vulcanite Optical Instrument Company, of that 
city, a microscopical department, under charge of E. Gundlach, 
formerly of Germany and late of Hackensack, N.J., exhibit a 
large series of entirely new designs. These are all of excellent 
workmanship, though of low or medium grade as to size, com- 
plexity, and cost. By simplifying the designs, introducing vul- 
canite into the mountings where it can be done to advantage, and 
introducing the business principle of attempting to create a large 
demand by production at a very low cost, the experiment of offer- 
ing good instruments at a very low rate is being tried on a scale 
and with facilities unprecedented in this country. The special 
peculiarities of these stands, aside from the vulcanite mountings, 
are the hinging of the sub-stage bar at the level of the object, con- 
testing in this respect the priority with Zentmayer’s new stand ; a 
new object carrier, which with some improvements may be conve- 
nient ; a new fine adjustment, by means of a screw acting on the 
body, which is supported at the end of two parallel horizontal 
springs, which allow a peculiarly smooth motion practically in- 
capable of deterioration from wear or any other probable cause ; 
and a coarse adjustment, consisting of a slide at the upper part of 
its course, and, below, a rapid screw which prevents pushing the 
body suddenly through the slide, and, without interfering with a 
prompt adjustment of low powers by sliding, gives a delicate adjust- 
ment for higher powers by screwing. This method is evidently a 
modification of Wale’s oblique slot. 
George Wale’s new student’s microscope is exhibited by the 
Stevens Institute of Technology. ‘This is indeed an educational 
microscope, and not a burlesque on the claim of the instrument to 
educational value. It is a small and compact stand, of the Con- 
tinental style, with horse-shoe base and low stage, of most sub- 
stantial workmanship, adopting the Zentmayer glass stage, and 
introducing an original coarse adjustment by means of a sliding 
