1876.] Microscopy at the International Exhibition. 729 
the object, contesting in this respect the priority with Zent- 
mayer’s new stand; a new object carrier, which with some im- 
provements may be convenient ; 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 incapable 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 adjustment for higher powers by 
screwing. This method is evidently a modification of Wales’ 
oblique slot. 
George Wales’ 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 
tube with the addition of a pin moving in an oblique slot and giv- 
ing a rapid and very steady and safe adjustment by means of a 
screwing movement, and an iris diaphragm capable of being used 
alter the continental plan close to the object slide, consisting of 
a thin split tube whose blades are overlapped ae 
Closed by being screwed up into a dome-shaped cavity 1m the bot- 
tom of the stage plate. The instrument is furnished with Wales’ 
excellent lenses. 
James W. Queen & Co. exhibit their instruments, which are 
of the English type, reduced and adapted to the student's micro- 
Scope grade, and aim rather to combine well-known scien 
mto a good and popular instrument, than to introduce novelties 
of construction. . 
The instruments by W. Y. McAllister, in the mere 
State Educational Exhibit, do not seem to suggest any of the 
_ Progress of recent years. ae 
A set of William Wales’ exquisite lenses was genes på 
Mr. Zentmayer, but was unfortunately allowed to be prematurely 
removed from the case isitor 
oe . . to 
| Several makers are conspicuous by their picesee® pr 
to this department would have been glad to see e as omni 
Powell, and Lealand, and the German makers, well repr ; 
ie aa NE y 
