306 NEW FIELD CARRIAGE (IRON) FOR LONG-RANGE GUNS. 
cumference. The flanges thus formed round the brackets replace the 
angle-irons employed to strengthen the existing carriages. 
The brackets are united by four transoms {a, b, c, d), two collar- 
bolts, through which pass two bolts, m andn, and a trail-eye-piece, p. 
They form a converging trail, their dimensions decreasing progressively 
towards the trail end; their outside depth being 14’6 ins. (about) at 
the trunnion holes, and 7'5 ins. at the end of the trail. Towards the 
breast of the carriage the trunnion-holes are strengthened by bands 
underneath, and closed by hinged cap-squares. 
The first transom is placed following the line oa } going obliquely 
from the trunnion holes to the axletree, on meeting which it bends and 
follows the lower edge of the brackets for a length of about 8 ins. 
Its upper part is hollowed out to receive the gun. 
The second transom is also placed obliquely following the line bb } 
starting from the rear extremity of the trunnion-hole bands and 
stopping at the lower edge of the brackets; it also is hollowed out 
for the same purpose as the first transom, to which it is nearly parallel. 
On the lower surface is placed a plate of sheet-iron, so as to form a 
sort of box. 
The third and fourth transoms follow the lines ce, dd, and serve also 
as transverse walls of a trail-box. The two first and the last transoms, 
(aa, bb } dd) are riveted by their edges to the brackets; the third differs— 
the lower edge alone is bent at right angles, the other edges of it are 
riveted to the bent edges of two strengthening plates, which, on the 
inside of the brackets, reinforce the sliding seat of the movable bolt, 
and the upper edge to a plate connecting the brackets at the top, near 
the elevating gear. This latter plate is cut out in front to allow room 
for the elevating gear, and its three other sides have their edges bent 
downwards, the long sides over the brackets and the rear side against 
the transom to which it is riveted. The connection between the 
brackets is, moreover, assured by two collar-bolts and a trail-piece. One 
of these collar-bolts, m, is placed near the elevating gear and the other 
near the trail-piece, where it also serves to secure the front ends of the 
handles. The trail-piece is of iron plate, about *25 in. thick, and riveted 
to the bent edges of the brackets; its lower part—prolonged towards 
the axletree to replace the usual transom—has an opening in which is 
fixed a bronze trail-eye, the lower face of which is rounded off, so as to 
facilitate limbering-up. 
The bottom of the trail-box, formed by the two lower transoms and 
the brackets, is formed of an iron plate fitted to the lower bent edges 
of the transoms, and riveted with them to the brackets; the lid is also 
formed of plate-iron, of which the long sides are bent over the brackets, 
while the short sides carry the hinges and the iron flaps necessary for 
opening and shutting the box, in which is placed the india-rubber buffer. 
The elevating gear is a double screw, similar to that in the service. 
The nut is not fixed on a special support, but is furnished with trunnions 
which rest on two bearings, q, of elliptical form riveted to the brackets. 
The right trunnion is pierced with a threaded hole, in which works a 
screw, having on the outside of the bracket a handle attached to it, e ; 
the other end rests against a piece of steel (s, Fig. 7) with threads 
corresponding to those of the nut, and movable in a bearing in the 
