Magnification, 4½ and 6½ diameters; Galilean type; object lens, 1¾ inches; interpupillary adjustment; tan leather finish; tan leather carrying case with compass; weight of glass, complete, with case, cord, and straps, 26 ounces; length of glass closed, 4½ inches. At a distance of 1,000 yards the field of view includes a diameter of 90 yards for the 4½ power, and 60 yards for the 6½ power. This glass is issued as a part of the fire-control equipment to field artillery. Price, $17.50.
Type C:
The type C is a high power glass of the porro prism type and is issued only to certain organizations of the field artillery, Signal Corps, and to all machine-gun platoons.
Description.—Magnification, 10 diameters; prismatic type; object lens, 1¾ inches; interpupillary adjustment; tan leather finish; sunshade; tan leather carrying case; weight of glass, complete, with case, cord, and straps, 46 ounces; length of glass closed, 7¾ inches. At a distance of 1,000 yards the field of view includes a diameter of 80 yards. This glass is issued to reconnaissance officers of field artillery. Price, $39.90.
Type D: Purchase has been made for delivery in the near future of a supply of a new type of high power prismatic field glass for sale and issue. This new type of glass, to be known as type D, is considerably smaller than the type C glass, as is shown by [figure 34]. The glass in a tan-colored carrying case weighs 15 ounces, the field glass without the case weighing but 9 ounces. The magnification is 8 powers and the field of view (with both eyes) 5° 40′. The estimated cost will be $27.
TELESCOPES ISSUED BY THE SIGNAL CORPS.
Type A: This glass complete consists of a 2-inch prism terrestrial telescope, powers 18 and 24, with alt-azimuth, folding tripod, and carrying case.
Type B: This telescope is a 19-27 power, 2-draw terrestrial telescope, in leather carrying case with sling. The leather carrying case also includes a holder which can be screwed into a tree, post, or other stationary wooden object.