considers the same facts in connexion with the early guns.
Favé states in his Histoire et tactique des trois armes (p. 23)
that during the invasion of Italy in 1494 by Charles VIII.
the guns were so unwieldy and the firing so slowRange and power.
that the damage caused by one shot could be repaired
before the next could be fired. The range, too, about
100 yds. for battering purposes, now seems absurdly short;
even at Waterloo 1200 yds. was all that separated the antagonists
at the commencement of the battle, but they approached to within
200 or 300 yds. without suffering serious loss from either musketry
or gun fire. Nelson fought his ships side by side with the enemy’s;
and fifty years after Nelson’s day a range of 1000 yds. at sea
was looked upon as an extreme distance at which to engage an
enemy. Contrast this with the range of 12,000 yds. at which the
opposing Russian and Japanese fleets more than once commenced
a naval battle in 1904, while
the critical part of the action
took place at a distance of
7000 yds.
These long ranges naturally intensified the requirements of the British and other navies, and, so that they shall not be outclassed and beaten by an enemy’s long-range fire, guns of continually increasing power are demanded. In 1900 a 12-in. gun of 40 calibres was considered all that was necessary. After the Russo-Japanese War the demand rose first for a 45-calibre gun and then for a 50-calibre gun, and muzzle velocities from about 2400 f.s. to about 3000 f.s. In 1910 greater shell power was demanded, to meet which new type guns of 13·5-in. and 14-in. calibre were being made.
In the days of M.L. heavy guns one of the most difficult problems was that of loading. The weight of the shell and powder was such that some mechanical power had to be employed for moving and ramming them home, and as hydraulic gear had by that date been introduced it was generally used for all loading operations. To load, the guns had to be run back until their muzzles were within the turret, or, in the case of the 16-in. 80-ton guns of H.M.S. “Inflexible,” until they were just outside the turret. The guns were then depressed to a fixed angle so as to bring the loading gear, which was protected below the gun deck, in line with the bore; the charge was first rammed home and then the projectile. With this arrangement, and in order to keep the turret of manageable dimensions, the guns had to be made short. Thus the 12·5-in. 38-ton M.L. gun had a length of bore of but 16 calibres, and the largest English service gun of 16-in. diameter had a bore of 18 calibres in length; while the largest of the type weighing 100 tons, built by Sir W. G. Armstrong & Co., for the Italian navy, had a bore of 17·72 in. and a length of 20 calibres. The rate of fire was fairly rapid—two rounds could be fired from one turret with the 12·5-in. guns in about three minutes, while it took about four minutes to fire the same number from the 80-ton and 100-ton gun turrets.
The possibility of double loading M.L. guns was responsible for the bursting on the 2nd January 1879 of a 38-ton gun in a turret on H.M.S. “Thunderer”; and it was partly due to this accident that B.L. guns were subsequently more favourably regarded in England, as it was argued that the double loading of a B.L. gun was an impossibility.
Fig. 45.—Breech Mechanism for 6-inch B.L. Gun
With the B.L. system guns gradually grew to be about 30 calibres in length of bore, and they were not made longer because this was considered a disadvantage, not to be compensated for by the small additional velocity which the old black and brown prismatic powders were capable of imparting with guns of greater length. Increase in the striking energy of the projectile was consequently sought by increasing the weight of the projectile, and, to carry this out with advantage, a gun of larger calibre had to be adopted. Thus the 12-in. B.L. gun of about 25 calibres in length gave place to the 13·5-in. gun of 30 calibres and weighing 67 tons, and to the 16·25-in. also of 30 calibres and weighing 111 tons. The 10,000- or 12,000-ton battleships carrying these enormous pieces were, judged by our present-day standard, far too small to carry such a heavy armament with their ponderous armoured machinery, which restricted the coal supply and rendered other advantages impossible; even the 24,000-ton battleships are none too large to carry the number of heavy guns now required to form the main armament.
The weight and size of the old brown prismatic charges had also reached huge dimensions; thus, while with heavy M.L. guns the weight of the full charge was about one-fourth that of the projectile, it had with heavy B.L. guns become one-half of the weight of the shell or even a greater proportion. The introduction of smokeless powder about 1890, having more than three times the amount of energy for the same weight of the older powders, allowed longer guns to be used, which fired a much smaller weight of charge but gave higher velocities; the muzzle or striking energy demanded for piercing hard-faced armour could consequently be obtained from guns of more moderate calibre. The 13·5-in. and 16·25-in. guns were therefore gradually discarded and new ships were armed with 12-in. guns of greater power. As the ballistic requirements are increased the weight of the charge becomes proportionately greater; thus for the
