...Railway artillery - Personal Page of GENE SLOVER

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attached. The recuperator cylinder, plates 405 and 406, is likewise
a separate cylinder carried in brackets cast on the cradle, and at the
rear on both sides it is pl8.!led to serve as a guide for the recoil lug, to
prevent rotation of the gun.
386. ELEVATING MECHANISM. -The elevating mechanism of this
mount is unique in several respects. Provision is made for elevating
the gun from 0 degrees, the loading angle, to 55 degrees. It is composed
of two straight racks, plate 407, driven through pinions, a
wormwheel, worm, a double speed transmission, sprockets and
chains, by four two-man handles, plates 408 and 409. The straight
racks slide in ways which are parallel to the inclined lower face of the
forward end of the side girders. It was necessary to put them in
this position to secure sufficient movement to elevate the gun to 55
degrees. At the lower end, they are connected with each other by
a heavy shaft, plate 407, to which are attached the two cqnnecting
rods running up to the bottom of the cradle. It will be observed,
plate" 409, that provision is made for two handles on each side of the
car, each for two men. A double speed transmission, similar in
design to those used on the 21 and 24 centimeter mounts is incorporated
in this mechanism. The ratio on the low gear is 4.125
turns of the handle for one degree of movement of the gun. One
man can operate the elevating mechanism with some difficulty at
low gear. It seems probable that eight men .could operate the high
gear without serious di1Jiculty. The gun and cradle were identical
with five others observed in the coast defenses of Belgium. On all
of the other guns, however, the elevating mechanism included
double telescoping screws .. It is probable that this gun when used
on a ship or in the coast defenses was likewise so elevated, and that
it was impossible to accommodate this mechanism on. a railway
mount and secure the elevation desired. It is likely that under the
specification of such an extreme elevation no other type of mechanism
could have been adapted to this cradle and mount without
serious difficulty. Judging from the diagram, plate 404, which was
made up from measurements of the gun and cradle and the estimated
length of recoil of 1.30 meters, it seems probable that the gun can
be fired from the track, the mount operating as a rolling mount, to
an elevation of 18 degrees, 30 minutes. If the length of recoil is
1.15 meters, as given in Gen. Arnoulde's report, it is probable that
an elevation of as much as 20 degrees can be secured. The gun can
be fired above 18 degrees only from a special emplacement.
387. TRAVERSING MECHANISM.-This mount is provided with a
car traversing mechanism installed on the front span bolster, giving
a maximum traverse of 1 degree on each side of center. This mechanism,
which includes the usual screw, plate 411, is operated through a
Digitized by Coogle