5. BAROMETERS ML-102-B, ML-102-E, and ML-102-F (fig.
1) . a. Frame
and case. These three barometers are shock-mounted in metal frames.
The case is secured to the schockmounts in the frame at the four cor-
ners with screws, washers, and nuts (fig. 10) . The barometer case con-
sists of a kettle-shaped brass housing over which is fitted a circular cast-
ing with four ears for mounting it to the frame. A plastic window in
this casting, held in place by a snap ring, protects the dial. A slotted
screw on the bottom side of the case enables the instrument to be ad-
justed without opening the case. A metal ring is provided at the top
of the frame for hanging the barometer. The back of the case of Bar-
ometer ML-102 -E has a metal rim which holds in place a nomograph
and temperature correction chart.
b. Dial (fig. 2). The dials
on the three instruments are identical.
Each is 5, inches in diameter and has three scales. The outer scale is
graduated in fiftieths (0.02) inches, with numerical designations for
whole inches from 26 to 31, and smaller numbers for tenths of inches.
The center scale is graduated in whole millibars from 1085 to 895 milli-
bars. The innermost scale is graduated from 895 to 745 millibars. Every
five millibars bears a numerical designation. In the center of the dial is
a shaft bearing an aluminum pointer which is flattened vertically at
the indicating end., Concentric with the scales and between the inch and
millibar scales is a mirror ring, the purpose of which is to reflect the
pointer and facilitate the reading of the scales (par. 10).
c. Aneroid mechanism (figs.
7 and 8). The aneroid
these barometers is built upon a casting which is mounted to a gear
plate, held in place by brackets and screws. The principle of operation
is the same m the three barometers, but the internal mechanism of
Barometer ML- 102-B differs considerably from that of Barometers
M L -102-E and ML-102-F. For a complete description of functioning
6. BAROMETERS ML-l02-D
AND ML-316/TM (fig.
1) . a. Case. These
instruments have identical wooden cases, painted olive drab, with metal
reinforcements at the outside corners. Means for hanging the barometer
temporarily is provided by a sliding metal hanger set flush with the
back of the case. (For preferred position of this barometer, see para-
graph 8C (2).) The lid is fastened to the case by separable hinges and