2900 | 5 | 08 | 6 | 25.2 | 7.75 | 7| 53| 7 | 892 ------+----+-----+----------+-------------+-------+--+---+-----------+-------- 3000 | 5 | 25 | 6 | 26.1 | 8.08 | 8| 20| 7 | 882 3100 | 5 | 42 | 6 | 27.0 | 8.40 | 8| 47| 6.5 | 872 3200 | 5 | 59 | 6 | 27.8 | 8.72 | 9| 15| 6 | 863 3300 | 6 | 17 | 6 | 28.7 | 9.05 | 9| 44| 6 | 854 3400 | 6 | 35 | 5 | 29.6 | 9.38 |10| 13| 5.5 | 845 ------+----+-----+----------+-------------+-------+--+---+-----------+-------- 3500 | 6 | 54 | 5 | 30.5 | 9.72 |10| 43| 5 | 836 3600 | 7 | 13 | 5 | 31.3 | 10.06 |11| 14| 5 | 827 3700 | 7 | 32 | 5 | 32.2 | 10.40 |11| 45| 5 | 819 3800 | 7 | 52 | 5 | 33.1 | 10.74 |12| 16| 4.5 | 811 3900 | 8 | 13 | 5 | 33.9 | 11.08 |12| 47| 4.5 | 803 ------+----+-----+----------+-------------+-------+--+---+-----------+-------- 4000 | 8 | 33 | 5 | 34.8 | 11.42 |13| 25| 4 | 796 4100 | 8 | 54 | 5 | 35.7 | 11.77 |14| 01| 4 | 788 4200 | 9 | 14 | 5 | 36.5 | 12.11 |14| 37| 4 | 781 4300 | 9 | 36 | 5 | 37.4 | 12.44 |15| 13| 3.5 | 774 4400 | 9 | 56 | 5 | 38.3 | 12.76 |15| 50| 3.5 | 768 4500 | 10 | 17 | 5 | 39.2 | 13.08 |16| 27| 3 | 762 ------+----+-----+----------+-------------+-------+--+---+-----------+-------- 3.6-INCH B L FIELD-MORTAR, MODEL 1890. (REVISED NOV. 11, 1892.) [Illustration: FIG. 50.] Metal steel Total length 2.05 feet Calibre 3.6 inches Weight 245 pounds Grooves 20 Twist of rifling {1 in 40 to {1 in 25 cal. Powder-chamber cylindrical Vent axial Muzzle velocity 650 ft.-sec. Maximum range 3450 yards It consists of a single piece of steel, the trunnions being forged solid with the piece. [Illustration: FIG. 51.] The breech mechanism, Fig. 51, is generally similar to that of the field-guns, except that the Freyre obturator is used, and in the locking arrangement the lever-handle is replaced by a bolt (_a_) which is turned by hand. This bolt operates the locking-stud on the left side of the block, and its handle bears also a vent-shield (_f_,) which keeps the vent closed until the breech is locked. THE CARRIAGE FOR 3.6-INCH B. L. MORTAR. [Illustration: FIG. 52.] This carriage, Fig. 52, is of cast steel and in one piece, and consists of a frame complete with transoms and soles.