The ordnance regulations of 1839 and the ordnance manual of 1841 brought in two distinctly new types of plates, the familiar brass oval waist-belt and cartridge-box plates with the letters "U. S." and the round shoulder-belt plate with the eagle. The oval plates fall into two general sizes, 3.5 inches by 2.2 inches (for plates on the infantry's cartridge box and the cavalry's waist belts)[98] and 2.8 inches by 1.6 inches (for plates on the infantry's waist belts and the cavalry's carbine cartridge boxes and pistol cartridge boxes). The use of each plate is determined by the type of fastener. These plates were struck in thin brass and the backs generally leaded, although some were used without such backing, probably to save both weight and material. Cartridge boxes were also embossed with the outline of this oval plate in lieu of the plate itself. It is interesting to note that the larger plates with lead backs weighed about 5-1/2 ounces and the smaller ones just over 2 ounces. [Footnote 98: The cavalry waist-belt plate is actually specified to be 3.6 inches by 2.2 inches.] WAIST-BELT PLATE, CAVALRY, 1839 _USNM 604408 (S-K 555). Figures 88, 89._ [Illustration: FIGURE 88] [Illustration: FIGURE 89] The specimen is oval, slightly convex, and struck in thin brass. The face has a raised edge and the letters "U S." The reverse is leaded, carries two studs and a hook (indicating its use), and is stamped with the maker's name, "W. H. Smith, Brooklyn." Smith is listed in New York City directories of the Civil War period as a contractor for metal and leather supplies. CARTRIDGE-BOX PLATE, INFANTRY, 1839 _USNM 604403 (S-K 550). Figure 90._ [Illustration: FIGURE 90] This plate is identical to the preceding one except that it is leaded and fitted with two looped-wire fasteners. The reverse is stamped with the name of the maker, "J. L. Pittman," who, like Smith, was a contractor in the New York City area in the Civil War period. CARTRIDGE-BOX PLATE, CAVALRY, 1839 _USNM 604395 (S-K 542). Not illustrated._ This is the oval "US" plate of the smaller size (2-3/4 by 1-1/8 in.), otherwise identical to the larger plate. It is fitted with two looped-wire fasteners. WAIST-BELT PLATE, INFANTRY, 1839 _USNM 604398 (S-K 545). Figure 91._ [Illustration: FIGURE 91] This specimen is identical to the preceding plate except that it is fitted with two brass hooks for attachment to the belt and the reverse is stamped with the maker's name, "Boyd & Sons." No trace of a manufacturer of such products by the name of Boyd has been found. It is probable that he worked during the Civil War period when there were many such contractors. WAIST-BELT PLATE, INFANTRY, 1839 _USNM 604399 (S-K 546). Not illustrated._ This plate is identical to those above except that the reverse is stamped with the maker's name. "H. A. Dingee." WAIST-BELT PLATE, INFANTRY, 1839 _USNM 604397 (S-K 544). Figure 92._ [Illustration: FIGURE 92]