Hotchkiss Revolving Cannon.pdf - Forgotten Weapons

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TilE IGllTS.
The rear sight.-rrhe rear sigltt (Plate V) cun::;i t::; of tho tem, slide,
and ·upport. The ·tem, uitahly graduated, is a traigbt piece of bra .·, tho
cro s-section being triangular with rounded corn •rs. The slide i' a , mall
box placed on the head of the stem, and capable of being moved perpendicularly
to it by mean, of a crew working in a. nut in it encl. This
screw terminates on the right in a milled head, and on the left in a journal
wlticlt revolves in the left end of the box. The shape of thi enJ. i · fini8hed
to corre. ponc1 to tlte other. 1\vo Ret- crews pas· through it into an
annular O'l'Oove in the journal. By thi · device the screw is only withdrawn
from the l>Ox when the set- crew are renewed. A plate is fa. tened
to the upper side of the b x, and Ita the ighting-notch and graduation on
it top and rear faces, respectively.
The support i · a lm1s. casting fastened to the rear of the right frame
bar, and is piercerl with a canal for the tern. A. top- crew, bearing ao·ainst
a flat 'pring, sen-eH to retain the stem at the desired elevation. The downward
tra,·el1s limited by a should r below the heaL! of the stem. T l1e ·topscrew
iu prevente 1 from being accidentally lo t by having a retainino·
.·boulder on its inner end. The screw is originally in e1ted tltrouglt the
chn.nnel formed in the prolongation of it bell. The head i · ·ubscq uentl.>'
fa ·tenecl to the screw.
shown in Fig. 7.
The rece in which the retaining :;houlder lies i ·
The front sight.-The front sight is a piece of steel divided into a
thren,ded ba e, a.n n.nnular shoulder, a.nd a hexagonal .tern, terminating ill
a cone. The latter i::; ronghenecl to prevent glare. The position of tlti:
sight varic , it hein