42 REPORT OF NEW JERSEY STATE MUSEUM. 
studied by visitors. Several smaller relief maps, some colored 
to represent geological features, gave in greater detail the 
topography of smaller areas. A complete set of the engraved 
topographical atlas sheets on a scale of one inch per mile, and 
of the larger-scale maps, 2,000 feet per inch, were on exhibi¬ 
tion, as well as a great number of special maps, engraved and 
manuscript, illustrating different topics, such as the relation 
of geology and topography, the distribution of water-powers, 
artesian wells, seaside resorts, changes of the coast line, etc., 
etc. 
The scenery of the State was shown by large photographs, 
some hung upon the wall, others arranged on an endless chain 
in a graphoscope, so that by turning a wheel they could be 
successively observed through a magnifying glass. 
The judges awarded a gold medal for the exhibit of maps 
and models. 
The study of thin rock sections under a microscope is a welb 
established and important branch of geologic investigation. 
In order that this phase of work might be brought to the at¬ 
tention of the public as well as to show the contrasted char¬ 
acter of the various rocks when seen by polarized light, a 
magazine microscope was designed by which a large number 
of rock sections fastened to an endless belt which travels on 
a revolving drum, can be brought successively across the field 
of vision. The drum is rotated by a thum screw, and by 
other screws the necesseary adjustment of the focus and the 
analyser can be obtained. The entire apparatus is enclosed 
in a case from which only the eye-piece of the microscope and 
the thumb screws project. About seventy-five different rock 
sections can be shown, and the entire apparatus is so arranged 
that it cannot readily get out of order. It attracted much 
attention from the general visitors and was warmly com¬ 
mended by several prominent museum workers. It received 
a silver medal. 
The preparation and installation of the general exhibit was 
in charge of S. H. Hamilton, who was assisted by C. B. Hard- 
enberg. The clay exhibit was prepared and installed under 
the direction of the State Geologist. After it was installed, 
Julius F. Kummel was in charge during the greater part of 
the Exposition period. It is not possible to mention by name 
