The trial couplings were applied to old and worn-out coal wagons, varying in relative heights and widths of buffers, and the tests were: 

1.  Coupling and uncoupling, and passing coupled round curves of less than two chains radius. 2.  Coupling under rapid transit movement and violent shock. 3.  Coupling under slow movement, the wagons being shunted together by two shunters. 4.  Wagons brought violently together while the coupling hooks were lifted out of action, to test the rigidity of the hooks in this position. 5.  Tested in competition with the ordinary coupling stock.

The trial was a success.  The new automatic coupling satisfactorily underwent the various conditions, and it was proved that:  1.  It can be lifted out of action with one hand and quite easily. 2.  It can be coupled and uncoupled six times as fast as with the pole hook in the daytime.  At night this advantage would be considerably increased.

The coupling is strong as well as elastic in its parts, and adjusts itself to the various conditions of traction.—­Engineering.

* * * * *

[Continued from supplement, No. 597, page 9539.]

MAGAZINE RIFLES.

Chaffee-Reece Magazine Rifle.—­We do not insert a drawing of this arm—­one of the three selected by the American board—­as it belongs to the same class and is similar in general construction to the Hotchkiss.  There is, however, an important difference in the magazine, which has no spiral spring, but is furnished instead with an ingenious system of ratchet bars.  One of these carries forward the cartridge a distance equal to its own length at each reciprocal motion of the bolt, while a second bar has no longitudinal motion, but prevents the cartridges from moving to the rear in the magazine tube after they have been moved forward by the other bar.  The magazine is loaded through an aperture in the butt plate, the opening of the spring cover of which causes the two ratchet bars to be depressed, so that the magazine can be filled by passing the cartridges along a smooth middle bar.  The act of closing the spring cover again brings the two ratchet bars into play.

[Illustration:  Fig. 9.—­Kropatschek magazine gun]

By means of a cut-off the ratchet bars can be prevented from acting, and the piece used as a single loader.

Kropatschek Magazine Rifle.—­This rifle, which is the small arm of the French navy, has a bolt-action rifle resembling the Gras (see Fig. 9).

The magazine is a brass tube underneath the barrel, as in the Winchester, Vetterli, Mauser, and other rifles of class 1.  It contains six cartridges, while a seventh can be placed in the trough or carrier, T.

When the breech is opened by pulling back the bolt, a projection on the latter strikes the carrier at N, causing its front extremity to raise the cartridge into the position shown in the section.  This movement is accelerated by the spring, A, acting against a knife-edge projection on the trough, T; in the upper position of the trough, the spring acts upon one face of the angle, and upon the other face when in the lower position.