======+=======+=========+==========+=========+=======+========= Weight|Bore in| Length |Weight of | Muzzle |Muzzle | Penet’n in |inches.| in |Projectile|Velocity.|Energy.| Iron at tons. | |Calibres.| lbs. | f.s. | f.t. +----+---- | | | | | |yds.|yds. | | | | | |2000|1000 ------+-------+---------+----------+---------+-------+----+---- 38 | 12.5 | 16 | 810 | 1575 | 13,930| 16 | 18 35 | 12 | 13½ | 707 | 1390 | 9470| 13 | 15 25 | 12 | 12 | 609 | 1288 | 7006| 11 | 12 25 | 11 | 12 | 544 | 1314 | 6560| 13 | 14 18 | 10 | 14½ | 406 | 1370 | 5360| 10 | 12 12½ | 9 | 14 | 253 | 1440 | 3695| 9 | 10 9 | 8 | 15 | 174 | 1384 | 2391| 7 | 8 6½ | 7 | 16 | 112 | 1325 | 1400| 6 | 7 ======+=======+=========+==========+=========+=======+====+==== In the early part of the period Armstrong breech-loaders up to 120 pounders had been in use, but the elementary breech blocks were so unsatisfactory that the Navy quickly discarded them, and adhered to muzzle-loaders long after all other Powers had given them up. The big muzzle loaders tabulated were of a very elementary type also. They were made by shrinking red hot wrought-iron collars over a steel tube; and it was never quite certain how far the interior would be affected. The projectiles never fitted accurately, with the result that there was considerable leakage of gas and very erratic firing. The rifling consisted of five or six grooves into which studs in the projectile fitted. In 1872 some experiments were carried out, the _Hotspur_ firing at the _Glatton’s_ turret at a range of 200 yards. The first shot missed altogether, the other two struck the turret, but not at the point aimed at. The turret was not appreciably damaged, though theoretically it should have been completely penetrated. This eventually led to the invention of an improved gas check--reference to which will be found at the end of the Barnaby Era. _UNARMOURED SHIPS OF THE ERA._