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PHYSICAL ANTHROPOLOGY. 
The section of Physical Anthropology is situated on the East 
and South Galleries of the East Court. On the East Gallery is 
the Anthropometric Laboratory. In this laboratory are anthro- 
pological and and psychological apparatus. The object of the 
group of psychological apparatus here exhibited is to illustrate 
the methods of making mental measurements, and tests to furnish 
an opportunity for accumulation of results in this direction. Upon 
the several tables are arranged apparatus for the study of the 
sensibility of the skin, the accuracy of the information obtained 
by movements, the judging of weights, and the limit of the sensa- 
tions of pain. 
In the field of sight, tests are made of the accuracy with 
which the lengths of lines can be judged, the accuracy with which 
spaces can be divided, the accuracy of aim or the coordination of 
the eye and mind, the accuracy with which lines may be copied, 
the quickness of perception in deducting small differences be- 
tween marks and the like. Optical tests are also made of the 
accuracy of the vision at a given distance, in the perception of 
form and also the delicacy of color and shade distinctions. 
More complex experiments attempt to determine the range 
and accuracy of the memory in its various forms and of the pow- 
ers of association. A special set of apparatus determines to the 
nearest hundredth of a second, the time needed in responding to 
sound or a touch, of the visual impression, also the time needed 
to choose between touches and visual impressions and to execute 
movements. A test of the accuracy and quickness of movement 
is also made. 
This apparatus was obtained for the Museum through Dr. 
Joseph Jastrow, Professor of Psychology in University of Wis- 
consin. 
There are also in the same room, apparatus for illustrating 
the law governing the distribution of individuals in a binomial 
curve, and for the drawing of the outlines of the various parts of 
the skeleton. In the smaller room adjoining are apparatus for 
taking the measurements of the body. 
On the South Gallery are situated cases containing the collec- 
tion of crania, skeletons, etc. 
