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 n.o.bel started the manufacture of nitroglycerin explosives in Europe. Smokeless powders came into use, the explosive properties of picric acid were discovered, and melanite, ballist.i.te, 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.
Still, black powder had many important uses. Its sensitivity to flame, high rate of combustion, and high temperature of explosion made it a very suitable igniter or "booster," to insure the complete ignition of the propellant. Further, it was the main element in such modern projectile fuzes as the ring fuze of the U. S. Field Artillery, which was long standard for bursts shorter than 25 seconds. This fuze was in the nose of the sh.e.l.l and consisted essentially of a plunger, primer, and rings grooved to hold a 9-inch train of compressed black powder.
To set the fuze, the fuze man merely turned a movable ring to the proper time mark. Turning the zero mark toward the channel leading to the sh.e.l.l"s bursting charge shortened the burning distance of the train, while turning zero away from the channel, of course, did the opposite. When the projectile left the gun, the shock made the plunger ignite the primer (compare fig. 42e) and fire the powder train, which then burned for the set time before reaching the sh.e.l.l charge. It was a technical improvement over the tubular sheet-iron fuze of the Venetians, but the principle was about the same.
[Ill.u.s.tration: Figure 21--MODERN POWDER TRAIN FUZE.]
THE CHARACTERISTICS OF CANNON
THE EARLY SMOOTHBORE CANNON
Soon after he found he could hurl a rock with his good right arm, man learned about trajectory--the curved path taken by a missile through the air. A baseball describes a "flat" trajectory every time the pitcher throws a hard, fast one. Youngsters tossing the ball to each other over a tall fence use "curved" or "high" trajectory. In artillery, where trajectory is equally important, there are three main types of cannon: (1) the flat trajectory gun, throwing shot at the target in relatively level flight; (2) the high trajectory mortar, whose sh.e.l.l will clear high obstacles and descend upon the target from above; and (3) the howitzer, an in-between piece of medium-high trajectory, combining the mobility of the fieldpiece with the large caliber of the mortar.
The Spaniard, Luis Collado, mathematician, historian, native of Lebrija in Andalusia, and, in 1592, royal engineer of His Catholic Majesty"s Army in Lombardy and Piedmont, defined artillery broadly as "a machine of infinite importance." Ordnance he divided into three cla.s.ses, admittedly following the rules of the "German masters, who were admired above any other nation for their founding and handling of artillery." Culverins and sakers (Fig. 23a) were guns of the first cla.s.s, designed to strike the enemy from long range. The battering cannon (fig. 23b) were second cla.s.s pieces; they were to destroy forts and walls and dismount the enemy"s machines. Third cla.s.s guns fired stone b.a.l.l.s to break and sink ships and defend batteries from a.s.sault; such guns included the pedrero, mortar, and bombard (fig. 23c, d).
Collado"s explanation of how the various guns were invented is perhaps naive, but nevertheless interesting: "Although the main intent of the inventors of this machine [artillery] was to fire and offend the enemy from both near and afar, since this offense must be in diverse ways it so happened that they formed various cla.s.ses in this manner: they came to realize that men were not satisfied with the _espingardas_ [small Moorish cannon], and for this reason the musket was made; and likewise the _esmeril_ and the falconet. And although these fired longer shots, they made the demisaker. To remedy a defect of that, the sakers were made, and the demiculverins and culverins. While they were deemed sufficient for making a long shot and striking the enemy from afar, they were of little use as battering guns because they fire a small ball. So they determined to found a second kind of piece, wherewith, firing b.a.l.l.s of much greater weight, they might realize their intention. But discovering likewise that this second kind of piece was too powerful, heavy and costly for batteries and for defense against a.s.saults or ships and galleys, they made a third cla.s.s of piece, lighter in metal and taking less powder, to fire b.a.l.l.s of stone. These are the commonly called _canones de pedreros_. All the cla.s.ses of pieces are different in range, manufacture and design. Even the method of charging them is different."
[Ill.u.s.tration: Figure 22--TRAJECTORIES. Maximum range of eighteenth century guns was about 1 mile.
_Guns could:_ Batter heavy construction with solid shot at long or short range; destroy fort parapets and, by ricochet fire, dismount cannon; shoot grape, canister, or bombs against ma.s.sed personnel.
_Mortars could:_ Reach targets behind obstructions; use high angle fire to shoot bombs, destroying construction and personnel.
_Howitzers could:_ Move more easily in the field than mortars; reach targets behind obstructions by high angle fire; shoot larger projectiles than could field guns of similar weight.]
It was most important for the artillerist to understand the different cla.s.ses of guns. As Collado quaintly phrased it, "he who ignores the present lecture on this _arte_ will, I a.s.sert, never do a good thing."
Cannon burst in the batteries every day because gunners were ignorant of how the gun was made and what it was meant to do. Nor was such ignorance confined to gunners alone. The will and whim of the prince who ordered the ordnance or "the simple opinion of the unexpert founder himself," were the guiding principles in gun founding. "I am forced," wrote Collado, "to persuade the princes and advise the founders that the making of artillery should always take into account the purpose each piece must serve." This persuasion he undertook in considerable detail.
[Ill.u.s.tration: Figure 23--SIXTEENTH CENTURY SPANISH ARTILLERY. Taken from a 1592 ma.n.u.script, these drawings ill.u.s.trate the three main cla.s.ses of artillery used by Spain during the early colonial period in the New World, a--Culverin (Cla.s.s 1). b--Cannon (Cla.s.s 2). c--Pedrero (Cla.s.s 3). d--Mortar (Cla.s.s 3).]
The first cla.s.s of guns were the long-range pieces, comparatively "rich" in metal. In the following table from Collado, the calibers and ranges for most Spanish guns of this cla.s.s are given, although as the second column shows, at this period calibers were standardized only in a general way. For translation where possible, and to list those which became the most popular calibers, we have added a final column.
Most of the guns were probably of culverin length: 30- to 32-caliber.
_Sixteenth century Spanish cannon of the first cla.s.s_
Name of Weight of Length Range in yards Popular gun ball of gun Point- Maximum caliber (pounds) (in calibers) blank
Esmeril 1/2 208 750 1/2-pounder esmeril.
Falconete 1 to 2 1-pounder falconet.
Falcon 3 to 4 417 2,500 3-pounder falcon.
Pasavolante 1 to 15 40 to 44 500 4,166 6-pounder pasavolante.
Media sacre 5 to 7 417 3,750 6-pounder demisaker.
Sacre 7 to 10 9-pounder saker.
Moyana 8 to 10 shorter than 9-pounder saker moyenne.
Media culebrina 10 to 18 833 5,000 12-pounder demiculverin.
Tercio de culebrina 14 to 22 18-pounder third-culverin.
Culebrina 20, 24, 25, 30 to 32 1,742 6,666 24-pounder culverin.
30, 40, 50 Culebrina real 24 to 40 30 to 32 32-pounder culverin royal.
Doble culebrina 40 and up 30 to 32 48-pounder culverin.
In view of the range Collado ascribes to the culverin, some remarks on gun performances are in order. "Greatest random" was what the old-time gunner called his maximum range, and random it was. Beyond point-blank range, the gunner was never sure of hitting his target. So with smoothbores, long range was never of great importance. Culverins, with their thick walls, long bores, and heavy powder charges, achieved distance; but second cla.s.s guns like field "cannon," with less metal and smaller charges, ranged about 1,600 yards at a maximum, while the effective range was hardly more than 500. Heavier pieces, such as the French 33-pounder battering cannon, might have a point-blank range of 720 yards; at 200-yard range its ball would penetrate from 12 to 24 feet of earthwork, depending on how "poor and hungry" the earth was.
At 130 yards a Dutch 48-pounder cannon put a ball 20 feet into a strong earth rampart, while from 100 yards a 24-pounder siege cannon would bury the ball 12 feet.
But generalizations on early cannon are difficult, for it is not easy to find two "mathematicians" of the old days whose ordnance lists agree. Spanish guns of the late 1500"s do, however, appear to be larger in caliber than pieces of similar name in other countries, as is shown by comparing the culverins: the smallest Spanish _culebrina_ was a 20-pounder, but the French great _coulevrine_ of 1551 was a 15-pounder and the typical English culverin of that century was an 18-pounder. Furthermore, midway of the 1500"s, Henry II greatly simplified French ordnance by holding his artillery down to the 33-pounder cannon, 15-pounder great culverin, 7-1/2-pounder b.a.s.t.a.r.d culverin, 2-pounder small culverin, a 1-pounder falcon, and a 1/2-pounder falconet. Therefore, any list like the one following must have its faults:
_Princ.i.p.al English guns of the sixteenth century_
Caliber Length Weight Weight Powder (inches) of gun of shot charge Ft. In. (pounds) (pounds) (pounds)
Rabinet 1.0 300 0.3 0.18 Serpentine 1.5 400 .5 .3 Falconet 2.0 3 9 500 1.0 .4 Falcon 2.5 6 0 680 2.0 1.2 Minion 3.5 6 6 1,050 5.2 3 Saker 3.65 6 11 1,400 6 4 Culverin b.a.s.t.a.r.d 4.56 8 6 3,000 11 5.7 Demiculverin 4.0 3,400 8 6 Basilisk 5.0 4,000 14 9 Culverin 5.2 10 11 4,840 18 12 Pedrero 6.0 3,800 26 14 Demicannon 6.4 11 0 4,000 32 18 b.a.s.t.a.r.d cannon 7.0 4,500 42 20 Cannon serpentine 7.0 5,500 42 25 Cannon 8.0 6,000 60 27 Cannon royal 8.54 8 6 8,000 74 30
Like many gun names, the word "culverin" has a metaphorical meaning.
It derives from the Latin _colubra_ (snake). Similarly, the light gun called _aspide_ or aspic, meaning "asp-like," was named after the venomous asp. But these digressions should not obscure the fact that both culverins and demiculverins were highly esteemed on account of their range and the effectiveness of fire. They were used for precision shooting such as building demolition, and an expert gunner could cut out a section of stone wall with these guns in short order.
As the fierce falcon hawk gave its name to the falcon and falconet, so the saker was named for the saker hawk; rabinet, meaning "rooster,"
was therefore a suitable name for the falcon"s small-bore cousin. The 9-pounder saker served well in any military enterprise, and the _moyana_ (or the French _moyenne_, "middle-sized"), being a shorter gun of saker caliber, was a good naval piece. The most powerful of the smaller pieces, however, was the _pasavolante_, distinguishable by its great length. It was between 40 and 44 calibers long! In addition, it had thicker walls than any other small caliber gun, and the combination of length and weight permitted an unusually heavy charge--as much powder as the ball weighed. A 6-pound lead ball was what the typical _pasavolante_ fired; another gun of the same caliber firing an iron ball would be a 4-pounder. The point-blank range of this Spanish gun was a football field"s length farther than either the falcon or demisaker.
In today"s Spanish, _pasavolante_ means "fast action," a phrase suggestive of the vicious impetuosity to be expected from such a small but powerful cannon. Sometimes it was termed a _drajon_, the English equivalent of which may be the drake, meaning "dragon"; but perhaps its most popular name in the early days was _cerbatana_, from Cerebus, the fierce three-headed dog of mythology. Strange things happen to words: a _cerbatana_ in modern Spanish is a pea shooter.
_Sixteenth century Spanish cannon of the second cla.s.s_
Spanish name Weight of ball Translation (pounds)
Quarto canon 9 to 12 Quarter-cannon.
Tercio canon 16 Third-cannon.
Medio canon 24 Demicannon.
Canon de abatir 32 Siege cannon.
Doble canon 48 Double cannon.
Canon de bateria 60 Battering cannon.
Serpentino Serpentine.
Quebrantamuro or lombarda 70 to 90 Wallbreaker or lombard.
Basilisco 80 and up Basilisk.
The second cla.s.s of guns were the only ones properly called "cannon"
in this early period. They were siege and battering pieces, and in some few respects were similar to the howitzers of later years. A typical Spanish cannon was only about two-thirds as long as a culverin, and the bore walls were thinner. Naturally, the powder charge was also reduced (half the ball"s weight for a common cannon, while a culverin took double that amount).
The Germans made their light cannon 18 calibers long. Most Spanish siege and battering guns had this same proportion, for a shorter gun would not burn all the powder efficiently, "which," said Collado, "is a most grievous fault." However, small cannon of 18-caliber length were too short; the muzzle blast tended to destroy the embrasure of the parapet. For this reason, Spanish demicannon were as long as 24 calibers and the quarter-cannon ran up to 28. The 12-pounder quarter-cannon, incidentally, was "culverined" or reinforced so that it actually served in the field as a demiculverin.
The great weight of its projectile gave the double cannon its name.
The warden of the Castillo at Milan had some 130-pounders made, but such huge pieces were of little use, except in permanent fortifications. It took a huge crew to move them, their carriages broke under the concentrated weight, and they consumed mountains of munitions. The lombard, which apparently originated in Lombardy, and the basilisk had the same disadvantages. The fabled basilisk was a serpent whose very look was fatal. Its namesake in bronze was tremendously heavy, with walls up to 4 calibers thick and a bore up to 30 calibers long. It was seldom used by the Europeans, but the Turkish General Mustafa had a pair of basilisks at the siege of Malta, in 1565, that fired 150- and 200-pound b.a.l.l.s. The 200-pounder gun broke loose as it was being transferred to a homeward bound galley and sank permanently to the bottom of the sea. Its mate was left on the island, where it became an object of great curiosity.
The third cla.s.s of ordnance included the guns firing stone projectiles, such as the pedrero (or perrier, petrary, cannon petro, etc.), the mortars, and the old bombards like Edinburgh Castle"s famous Mons Meg. Bars of wrought iron were welded together to form Meg"s tube, and iron rings were clamped around the outside of the piece. In spite of many accidents, this coopering technique persisted through the fifteenth century. Mons Meg was made in two sections that screwed together, forming a piece 13 feet long and 5 tons in weight.