Figure 48—LOADING A CANNON.
Muzzle-loading smoothbore cannon were used for almost 700 years.
The old-time gunner was not only an artist, vastly superior to the average soldier, but, when circumstances permitted, he performed his wizardry with all due ceremony. Diego Ufano, Governor of Antwerp, watched a gun crew at work about 1500:
"The piece having arrived at the battery and being provided with all needful materials, the gunner and his assistants take their places, and the drummer is to beat a roll. The gunner cleans the piece carefully with a dry rammer, and in pulling out the said rammer gives a dab or two to the mouth of the piece to remove any dirt adhering." (At this point it was customary to make the sign of the cross and invoke the intercession of St. Barbara.)
"Then he has his assistant hold the sack, valise, or box of powder, and filling the charger level full, gives a slight movement with the other hand to remove any surplus, and then puts it into the gun as far as it will go. Which being done, he turns the charger so that the powder fills the breech and does not trail out on the ground, for when it takes fire there it is very annoying to the gunner." (And probably to the gentleman holding the sack.)
"After this he will take the rammer, and, putting it into the gun, gives two or three good punches to ram the powder well in to the chamber, while his assistant holds a finger in the vent so that the powder does not leap forth. This done, he takes a second charge of powder and deposits it like the first; then puts in a wad of straw or rags which will be well packed to gather up all the loose powder. This having been well seated with strong blows of the rammer, he sponges out the piece.
"Then the ball, well cleaned by his assistant, since there is danger to the gunner in balls to which sand or dirt adhere, is placed in the piece without forcing it till it touches gently on the wad, the gunner being careful not to hold himself in front of the gun, for it is silly to run danger without reason. Finally he will put in one more wad, and at another roll of drums the piece is ready to fire."
Maximum firing rate for field pieces in the early days was eight rounds an hour. It increased later to 100 rounds a day for light guns and 30 for heavy pieces. (Modern non-automatic guns can fire 15 rounds per minute.) After about 40 rounds the gun became so hot it was unsafe to load, whereupon it was "refreshed" with an hour's rest.
Figure 48—LOADING A CANNON.
Muzzle-loading smoothbore cannon were used for almost 700 years.
Approved aiming procedure was to make the first shot surely short, in order to have a measurement of the error. The second shot would be at greater elevation, but also cautiously short. After the third round, the gunner could hope to get hits. Beginners were cautioned against the desire to hit the target at the first shot, for, said a celebrated artillerist, "... you will get overs and cannot estimate how much over."
As gunners gradually became professional soldiers, gun drills took on a more military aspect, as these seventeenth century commands show:
Gunners had no trouble finding work, as is singularly illustrated by the case of Andrew Ransom, a stray Englishman captured near St. Augustine in the late 1600's. He was condemned to death. The executional device failed, however, and the padres in attendance took it as an act of God and led Ransom to sanctuary at the friary. Meanwhile, the Spanish governor learned this man was an artillerist and a maker of "artificial fires." The governor offered to "protect" him if he would live at the Castillo and put his talents to use. Ransom did.
Figure 49—A SIEGE BOMBARD OF THE 1500's.
By 1800, although guns could be served with as few as three men, efficient drill usually called for a much larger force. The smallest crew listed in the United States Navy manual of 1866 was seven: first and second gun captains, two loaders, two spongers, and a "powder monkey" (powder boy). An 11-inch pivot-gun on its revolving carriage was served by 24 crewmen and a powderman. In the field, transportation for a 24-pounder siege gun took 10 horses and 5 drivers.
Twelve rounds an hour was good practice for heavy guns during the Civil War period, although the figure could be upped to 20 rounds. By this date, of course, although the principles of muzzle loading had not changed, actual loading of the gun was greatly simplified by using fixed and semi-fixed ammunition. Loading technique varied with the gun, but the following summary of drill from the United States Heavy Ordnance Manual of 1861 gives a fair idea of how the crew handled a siege gun:
In the first place, consider that the equipment is all in its proper place. The gun is on a two-wheeled siege carriage, and is "in battery," or pushed forward on the platform until the muzzle is in the earthwork embrasure. On each side of the gun are three handspikes, leaning against the parapet. On the right of the gun a sponge and a rammer are laid on a prop, about 6 feet away from the carriage. Near the left muzzle of the gun is a stack of cannonballs, wads, and a "passbox" or powder bucket. Hanging from the cascabel are two pouches: the tube-pouch containing friction "tubes" (primers for the vent) and the lanyard; and the gunner's pouch with the gunner's level, breech-sight, pick, gimlet, vent-punch, chalk, and fingerstall (a leather cover for the gunner's second left finger when the gun gets hot). Under the wheels are two chocks; the vent-cover is on the vent, a tompion in the muzzle; a broom leans against the parapet beyond the stack of cannonballs. A wormer, ladle, and wrench were also part of the battery equipment.
The crew consisted of a gunner and six cannoneers. At the command Take implements the gunner stepped to the cascabel and handed the vent-cover to No. 2; the tube-pouch he gave to No. 3; he put on his fingerstall, leveled the gun with the elevating screw, applied his level to base ring and muzzle to find the highest points of the barrel, and marked these points with chalk for a line of sight. His six crewmen took their positions about a yard apart, three men on each side of the gun, with handspikes ready.
From battery was the first command of the drill. The gunner stepped from behind the gun, while the handspikemen embarred their spikes. Cannoneers Nos. 1, 3, and 5 were on the right side of the gun, and the even-numbered men were on the left. Nos. 1 and 2 put their spikes under the front of the wheels; Nos. 3 and 4 embarred under the carriage cheeks to bear down on the rear spokes of the wheel; Nos. 5 and 6 had their spikes under the maneuvering bolts of the trail for guiding the piece away from the parapet. With the gunner's word Heave, the men at the wheels put on the pressure, and with successive heaves the gun was moved backward until the muzzle was clear of the embrasure by a yard. The crew then unbarred, and Nos. 1 and 2 chocked the wheels.
Figure 50—GUN DRILL IN THE 1850's.
Load was the second command. Nos. 1, 2, and 4 laid down their spikes; No. 2 took out the tompion; No. 1 took up the sponge and put its wooly head into the muzzle; No. 2 stepped up to the muzzle and seized the sponge staff to help No. 1. In five counts they pushed the sponge to the bottom of the bore. Meanwhile, No. 4 took the passbox and went to the magazine for a cartridge.
The gunner put his finger over the vent, and with his right hand turned the elevating screw to adjust the piece conveniently for loading. No. 3 picked up the rammer.
At the command Sponge, the men at the sponge pressed the tool against the bottom of the bore and gave it three turns from right to left, then three turns from left to right. Next the sponge was drawn, and while No. 1 exchanged it for No. 3's rammer, the No. 2 man took the cartridge from No. 4, and put it in the bore. He helped No. 1 push it home with the rammer, while No. 4 went for a ball and, if necessary, a wad.
Ram! The men on the rammer drew it out an arm's length and rammed the cartridge with a single stroke. No. 2 took the ball from No. 4, while No. 1 threw out the rammer. With the ball in the bore, both men again manned the rammer to force the shot home and delivered a final single-stroke ram. No. 1 put the rammer back on its prop. The gunner stuck his pick into the vent to prick open the powder bag.
The command In battery was the signal for the cannoneers to man the handspikes again, Nos. 1, 2, 3, and 4 working at the wheels and Nos. 5 and 6 guiding the trail as before. After successive heaves, the gunner halted the piece with the wheels touching the hurter—the timber laid at the foot of the parapet to stop the wheels.
Point was the next order. No. 3, the man with the tube-pouch, got out his lanyard and hooked it to a primer. Nos. 5 and 6 put their handspikes under the trail, ready to move the gun right or left. The gunner went to the breech of the gun, removed his pick from the vent, and, sighting down the barrel, directed the spikemen: he would tap the right side of the breech, and No. 5 would heave on his handspike to inch the trail toward the left. A tap on the left side would move No. 6 in the opposite direction. Next, the gunner put the breech-sight (if he needed it) carefully on the chalk line of the base ring and ran the elevating screw to the proper elevation.
As soon as the gun was properly laid, the gunner said Ready and signaled with both hands. He took the breech-sight off the gun and walked over to windward, where he could watch the effect of the shot. Nos. 1 and 2 had the chocks, ready to block the wheels at the end of the recoil. No. 3 put the primer in the vent, uncoiled the lanyard and broke a full pace to the rear with his left foot. He stretched the lanyard, holding it in his right hand.
At Fire! No. 3 gave a smart pull on the lanyard. The gun fired, the carriage recoiled, and Nos. 1 and 2 chocked the wheels. No. 3 rewound his lanyard, and the gunner, having watched the shot, returned to his post.
The development of heavy ordnance through the ages is a subject with many fascinating ramifications, but this survey has of necessity been brief. It has only been possible to indicate the general pattern. Most of the interesting details must await the publication of much larger volumes. It is hoped, however, that enough information has been included herein to enhance the enjoyment that comes from inspecting the great variety of cannon and projectiles that are to be seen throughout the National Park System.
With Rodman's gun, the muzzle-loading smoothbore was at the apex of its development. Through the years great progress had been made in mobility, organization, and tactics. Now a new era was beginning, wherein artillery surpassed even the decisive role it had under Gustavus Adolphus and Napoleon. In spite of new infantry weapons that forced cannon ever farther to the rear, artillery was to become so deadly that its fire caused over 75 percent of the battlefield casualties in World War I.
Many of the vital changes took place during the latter years of the 1800's, as rifles replaced the smoothbores. Steel came into universal use for gun founding; breech and recoil mechanisms were perfected; smokeless powder and high explosives came into the picture. Hardly less important was the invention of more efficient sighting and laying mechanisms.
The changes did not come overnight. In Britain, after breechloaders had been in use almost a decade, the ordnance men went back to muzzle-loading rifles; faulty breech mechanisms caused too many accidents. Not until one of H.M.S. Thunderer's guns was inadvertently double-loaded did the English return to an improved breechloader.
The steel breechloaders of the Prussians, firing two rounds a minute with a percussion shell that broke into about 30 fragments, did much to defeat the French (1870-71). At Sedan, the greatest artillery battle fought prior to 1914, the Prussians used 600 guns to smother the French army. So thoroughly did these guns do their work that the Germans annihilated the enemy at the cost of only 5 percent casualties. It was a demonstration of using great masses of guns, bringing them quickly into action to destroy the hostile artillery, then thoroughly "softening up" enemy resistance in preparation for the infantry attack. While the technical progress of the Prussian artillery was considerable, it was offset in large degree by the counter-development of field entrenchment.
As the technique of forging large masses of steel improved, most nations adopted built-up (reinforcing hoops over a steel tube) or wire-wrapped steel construction for their cannon. With the advent of the metal cartridge case and smokeless powder, rapid-fire guns came into use. The new powder, first used in the Russo-Turkish War (1877-78), did away with the thick white curtain of smoke that plagued the gunner's aim, and thus opened the way for production of mechanisms to absorb recoil and return the gun automatically to firing position. Now, gunners did not have to lay the piece after every shot, and the rate of fire increased. Shields appeared on the gun—protection that would have been of little value in the days when gunners had to stand clear of a back-moving carriage.
During the early 1880's the United States began work on a modern system of seacoast armament. An 8-inch breech-loading rifle was built in 1883, and the disappearing carriage, giving more protection to both gun and crew, was adopted in 1886. Only a few of the weapons were installed by 1898; but fortunately the overwhelming naval superiority of the United States helped bring the War with Spain to a quick close.
Figure 15—Ranges.
During this war, United States forces were equipped with a number of British 2.95-inch mountain rifles, which, incidentally, served as late as World War II in the pack artillery of the Philippine Scouts. Within the next few years the antiquated pieces such as the 3-inch wrought-iron rifle, the 4.2-inch Parrott siege gun, converted Rodmans, and the 15-inch Rodman smoothbore were finally pushed out of the picture by new steel guns. There were small-caliber rapid-fire guns of different types, a Hotchkiss 1.65-inch mountain rifle, and Hotchkiss and Gatling machine guns. The basic pieces in field artillery were 3.2- and 3.6-inch guns and a 3.6-inch mortar. Siege artillery included a 5-inch gun, 7-inch howitzers, and mortars. In seacoast batteries were 8-, 10-, 12-, 14-, and 16-inch guns and 12-inch mortars of the primary armament; intermediate rapid-fire guns of 4-, 4.72-, 5-, and 6-inch calibers; and 6- and 15-pounder rapid-fire guns in the secondary armament.
The Japanese showed the value of the French system of indirect laying (aiming at a target not visible to the gunner) during the Russo-Japanese War (1904-05). Meanwhile, the French 75-mm. gun of 1897, firing 6,000 yards, made all other field artillery cannon obsolete. In essence, artillery had assumed the modern form. The next changes were wrought by startling advances in motor transport, signal communications, chemical warfare, tanks, aviation, and mass production.
Aside from gradual improvement in the formula, no great change in powder making came until 1860, when Gen. Thomas J. Rodman of the U. S. Ordnance Department began to tailor the powder to the caliber of the gun. The action of ordinary cannon powder was too sudden. The whole charge was consumed before the projectile had fairly started on its way, and the strain on the gun was terrific. Rodman compressed powder into disks that fitted the bore of the gun. The disks were an inch or two thick, and pierced with holes. With this arrangement, a minimum of powder surface was exposed at the beginning of combustion, but as the fire ate the holes larger (compare fig. 20f), the burning area actually increased, producing a greater volume of gas as the projectile moved forward. Rodman thus laid the foundation for the "progressive burning" pellets of modern powders (fig. 20).
Figure 20—MODERN GANNON POWDER.
A powder grain has the characteristics of an explosive only when it is confined. Modern propellants are low explosives (that is, relatively slow burning), but projectiles may be loaded with high explosive, a—Flake, b—Strip, c—Pellet, d—Single perforation, e—Standard, 7-perforation, f—Burning grain of 7-perforation type. Ideally, the powder grain should burn progressively, with continuously increasing surface, the grain being completely consumed by the time the projectile leaves the bore, g—Walsh grain.
For a number of reasons General Rodman did not take his "perforated cake cartridge" beyond the experimental stage, and his "Mammoth" powder, such a familiar item in the powder magazines of the latter 1800's, was a compromise. As a block of wood burns steadier and longer than a quick-blazing pile of twigs, so the 3/4-inch grains of mammoth powder gave a "softer" explosion, but one with more "push" and more uniform pressure along the bore of the gun.
It was in the second year of the Civil War that Alfred Nobel started the manufacture of nitroglycerin explosives in Europe. Smokeless powders came into use, the explosive properties of picric acid were discovered, and melanite, ballistite, and cordite appeared in the last quarter of the century, so that by 1890 nitrocellulose and nitroglycerin-base powders had generally replaced black powder as a propellant.
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