The United States Army Hospital Model microscope
was manufactured by the optician and scientific instrument maker
Joseph Zentmayer of Philadelphia. It was first introduced in
1862-1863 for use by the U.S.A. Medical Department during the Civil
War. It continued to be sold to the government as well as to the
civilian market until the end of the 19th century. Over that time
span, the microscope incorporated a number of modification and
improvements. The four examples below are illustrative of some of
these changes.
Monocular: serial
no. 975
prior to 1876
(click
on the above image for additional photos)
Binocular: serial
no. 723
prior to 1876
(click
on the above image for additional photos)
Monocular: serial
no. 1867
c. 1877
(click
on the above image for additional photos)
Binocular: serial
no. 3773
after 1876
(click
on the above image for additional photos)