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[Additional notes] will be found near the end of this ebook.

THE
PROJECTILE-THROWING ENGINES
OF THE ANCIENTS
AND
TURKISH AND OTHER ORIENTAL BOWS
OF MEDIÆVAL AND LATER TIMES

By the same Author.

THE CROSSBOW,
MEDIÆVAL AND MODERN, MILITARY AND SPORTING:
Its Construction, History, and Management.
WITH A TREATISE ON
THE BALISTA AND CATAPULT OF THE ANCIENTS.
With 220 Illustrations. Medium 4to. 63s. net.

LONGMANS, GREEN, & CO., 39 Paternoster Row, London,
New York, Bombay, and Calcutta.

A SUMMARY OF

THE HISTORY, CONSTRUCTION AND
EFFECTS IN WARFARE
OF THE
PROJECTILE-THROWING
ENGINES
OF THE ANCIENTS
WITH A TREATISE ON THE
STRUCTURE, POWER AND MANAGEMENT
OF
TURKISH AND OTHER ORIENTAL BOWS
OF MEDIÆVAL AND LATER TIMES

BY
SIR RALPH PAYNE-GALLWEY, B^T.

FORTY ILLUSTRATIONS

LONGMANS, GREEN, AND CO.
39 PATERNOSTER ROW, LONDON
NEW YORK, BOMBAY, AND CALCUTTA
1907
All rights reserved

THE PROJECTILE-THROWING ENGINES OF
THE ANCIENTS

CONTENTS

PREFACE

Since my recent book on mediæval archery and ancient weapons was issued,[1] I have obtained a considerable amount of information concerning the projectile engines of the Greeks and Romans. I now print a concise account of the history, construction and effects in warfare of these engines.

In this summary the additional notes I have acquired are included.

I also append a treatise fully describing that remarkable weapon the Turkish composite bow, which I only cursorily dealt with in the work referred to.

R. P. G.

Thirkleby Park,
Thirsk:
Dec. 1906.

[1] The Crossbow, Mediæval and Modern, Military and Sporting: its Construction, History, and Management. With a Treatise on the Balista and Catapult of the Ancients. 220 illustrations. Messrs. Longmans & Co., 39 Paternoster Row, London.

PART I
INTRODUCTORY NOTES ON ANCIENT PROJECTILE ENGINES

Of ancient Greek authors who have left us accounts of these engines, Heron (284–221 B.C.) and Philo (about 200 B.C.) are the most trustworthy.

Both these mechanicians give plans and dimensions with an accuracy that enables us to reconstruct the machines, if not with exactitude at any rate with sufficient correctness for practical application.

Though in the books of Athenæus, Biton, Apollodorus, Diodorus, Procopius, Polybius and Josephus we find incomplete descriptions, these authors, especially Josephus, frequently allude to the effects of the engines in warfare; and scanty as is the knowledge they impart, it is useful and explanatory when read in conjunction with the writings of Heron and Philo.

Among the Roman historians and military engineers, Vitruvius and Ammianus are the best authorities.

Vitruvius copied his descriptions from the Greek writers, which shows us that the Romans adopted the engines from the Greeks.

Of all the old authors who have described the engines, we have but copies of the original writings. It is therefore natural that we should come across many phrases and drawings which are evidently incorrect, as a result of repeated transcription, and which we know to be at fault though we cannot actually prove them to be so.

With few exceptions, all the authors named simply present us with their own ideas when they are in doubt respecting the mechanical details and performances of the engines they wish to describe.

All such spurious information is, of course, more detrimental than helpful to our elucidation of their construction and capabilities.

It frequently happens that in a mediæval picture of one of these machines some important mechanical detail is omitted, or, from the difficulty of portraying it correctly, is purposely concealed by figures of soldiers, an omission that may be supplied by reference to other representations of the same weapon.

Fig. 1.—Besieging a fortified Town with a Battery of Catapults and Balistas.

Criticism.—In this picture the balistas are fairly correct, but the catapults are too small.

From Polybius. Edition 1727.

It is, indeed, impossible to find a complete working plan of any one of these old weapons, a perfect design being only obtainable by consulting many ancient authorities, and, it may be said, piecing together the details of construction they individually give.

* * * * *

We have no direct evidence as to when the engines for throwing projectiles were invented.

It does not appear that King Shalmaneser II. of Assyria (859–825 B.C.) had any, for none are depicted on the bronze doors of the palace of Balâwat, now in the British Museum, on which his campaigns are represented, though his other weapons of attack and defence are clearly shown.

The earliest allusion is the one in the Bible, where we read of Uzziah, who reigned from B.C. 808–9 to B.C. 756–7. ‘Uzziah made in Jerusalem engines invented by cunning men, to be on the towers and upon the bulwarks, to shoot arrows and great stones withal.’ (2 Chronicles xxvi. 15.)

Diodorus tells us that the engines were first seen about 400 B.C., and that when Dionysius of Syracuse organised his great expedition against the Carthaginians (397 B.C.) there was a genius among the experts collected from all over the world, and that this man designed the engines that cast stones and javelins.

From the reign of Dionysius and for many subsequent centuries, or till near the close of the fourteenth, projectile-throwing engines are constantly mentioned by military historians.

But it was not till the reign of Philip of Macedon (360–336 B.C.) and that of his son Alexander the Great (336–323 B.C.) that their improvement was carefully attended to and their value in warfare fully recognised.

As before stated, the Romans adopted the engines from the Greeks.

Vitruvius and other historians tell us this, and even copy their descriptions of them from the Greek authors, though too often with palpable inaccuracy.

To ascertain the power and mechanism of these ancient engines a very close study of all the old authors who wrote about them is essential, with a view to extracting here and there useful facts amid what are generally verbose and confused references.

There is no doubt that the engines made and used by the Romans after their conquest of Greece (B.C. 146), in the course of two or three centuries became inferior to the original machines previously constructed by the Greek artificers.

Their efficiency chiefly suffered because the art of manufacturing their important parts was gradually neglected and allowed to become lost.

Fig. 2.—A Siege.

Criticism.—The picture is open to the spectator in order that he may see both defenders and besiegers at work.

The besieged have just cast a stone from a catapult. The stone is falling on the movable tower belonging to the attacking side.

From Polybius. Edition 1727.

For instance, how to make the skein of sinew that bestowed the very life and existence on every projectile-casting engine of the ancients.

The tendons of which the sinew was composed, the animals from which it was taken, and the manner in which it was prepared, we can never learn now.

Every kind of sinew, or hair or rope, with which I have experimented, either breaks or loses its elasticity in a comparatively short time, if great pressure is applied. It has then to be renewed at no small outlay of expense and trouble. Rope skeins, with which we are obliged to fit our models, cannot possibly equal in strength and above all in elasticity, skeins of animal sinew or even of hair.

The formation of the arm or arms of an engine, whether it is a catapult with its single upright arm or a balista with its pair of lateral ones, is another difficulty which cannot now be overcome, for we have no idea how these arms were made to sustain the great strain they had to endure.

We know that the arm of a large engine was composed of several spars of wood and lengths of thick sinew fitted longitudinally, and then bound round with broad strips of raw hide which would afterwards set nearly as hard and tight as a sheath of metal.

We know this, but we do not know the secret of making a light and flexible arm of sufficient strength to bear such a strain as was formerly applied to it in a catapult or a balista.

Certainly, by shaping an arm of great thickness we can produce one that will not fracture, but substance implies weight, and undue weight prevents the arm from acting with the speed requisite to cast its projectile with good effect.

A heavy and ponderous arm of solid wood cannot, of course, rival in lightness and effectiveness a composite one of wood, sinew and hide.

The former is necessarily inert and slow in its action of slinging a stone, while the latter would, in comparison, be as quick and lively as a steel spring.

When the art of producing the perfected machines of the Greeks was lost, they were replaced by less effective contrivances.

If the knowledge of constructing the great catapult of the ancients in its original perfection had been retained, such a clumsy engine as the mediæval trebuchet would never have gained popularity. The trebuchet derived its power from the gravity of an immense weight at one end of its pivoted arm tipping up the other end, to which a sling was attached for throwing a stone.

As regards range, there could be no comparison between the efficiency of a trebuchet, however large, as worked merely by a counterpoise, and that of an engine deriving its power from the elasticity of an immense coil of tightly twisted sinew.

It is certain that if the latter kind of engine had survived in its perfect state the introduction of cannon would have been considerably delayed, for the effects in warfare of the early cannon were for a long period decidedly inferior to those of the best projectile engines of the ancients.

Notwithstanding many difficulties, I have succeeded in reconstructing, though of course on a considerably smaller scale, the chief projectile throwing engines of the ancients, and with a success that enables them to compare favourably, as regards their range, with the Greek and Roman weapons they represent.

Still, my engines are by no means perfect in their mechanism, and are, besides, always liable to give way under the strain of working.

One reason of this is that all modern engines of the kind require to be worked to their utmost capacity, i.e. to the verge of their breaking point, to obtain from them results that at all equal those of their prototypes.

A marked difference between the ancient engines and their modern imitations, however excellent the latter may be, is, that the former did their work easily, and well within their strength, and thus without any excessive strain which might cause their collapse after a short length of service.[2]

[2] Again, though my largest catapult will throw a stone to a great distance it cannot throw one of nearly the weight it should be able to do, considering the size of its frame, skein of cord and mechanism. In this respect it is decidedly inferior to the ancient engine.

The oft-disputed question as to the distance to which catapults and balistas shot their projectiles can be solved with approximate accuracy by comparing their performances—as given by ancient military writers—with the results obtainable from modern reproductions.

While treating of this matter we should carefully consider the position and surroundings of the engines when engaged in a siege, and especially the work for which they were designed.

As an example, archers, with the advantage of being stationed on high towers and battlements, would be well able to shoot arrows from 270 to 280 yards. For this reason it was necessary for the safe manipulation of the attacking engines that they should be placed at about 300 yards from the outer walls of any fortress they were assailing.

As a catapult or a balista was required not only to cast its missile among the soldiers on the ramparts of a fortified place, but also to send it clear over the walls amid the houses and people within the defences, it is evident that the engines must have had a range of from 400 to 500 yards, or more, to be as serviceable and destructive as they undoubtedly were.

Josephus tells us that at the siege of Jerusalem, A.D. 70 (‘Wars of the Jews,’ Book V. Chapter VI.), stones weighing a talent (57¾ lbs. avoirdupois) were thrown by the catapults to a distance of two or more ‘stades.’

This statement may be taken as trustworthy, for Josephus relates what he personally witnessed and his comments are those of a commander of high rank and intelligence.

Fig. 3.—A Fortified Town being Bombarded by a Catapult.

Criticism.—The stones thrown by the besieged may be seen falling in the trenches of the besiegers. The catapult depicted is drawn on much too small a scale.

From Polybius. Edition 1727.

Two or more ‘stades,’ or let us say 2 to 2¼ ‘stades,’ represent 400 to 450 yards. Remarkable and conclusive testimony confirming the truth of what we read in Josephus is the fact that my largest catapult—though doubtless much smaller and less powerful than those referred to by the historian—throws a stone ball of 8 lbs. in weight to a range of from 450 to nearly 500 yards.

It is easy to realise that the ancients, with their great and perfect engines fitted with skeins of sinew, could cast a far heavier stone than one of 8 lbs., and to a longer distance than 500 yards.

Agesistratus,[3] a Greek writer who flourished B.C. 200, and who wrote a treatise on making arms for war, estimated that some of the engines shot from 3½ to 4 ‘stades’ (700 to 800 yards).

[3] The writings of Agesistratus are non-extant but are quoted by Athenæus.

Though such a very long flight as this appears almost incredible, I can adduce no sound reason for doubting its possibility. From recent experiments I am confident I could now build an engine of a size and power to accomplish such a feat if light missiles were used, and if its cost were not a consideration.

Fig. 4.—A Siege Catapult (without a sling).

From Polybius. Edition 1727.

PART II
THE CATAPULT (WITH A SLING)

Fig. 5.—A Siege Catapult (without a sling).

Criticism.—This engine was moved into position on rollers and then props were placed under its sides to adjust the range of the projectile.

The end of the arm was secured by the notch of the large iron catch and was released by striking down the handle of the catch with a heavy mallet.

The arm is, however, too long for the height of the cross-bar against which it strikes and would probably break off at its centre.

The hollow for the stone is much too large, as a stone big enough to fit it could not be cast by a weapon of the dimensions shown in the picture.

From an Illustrated Manuscript, Fifteenth Century (No. 7239), Bibl. Nat. Paris.

The mediæval catapult was usually fitted with an arm that had a hollow or cup at its upper end in which was placed the stone it projected, as shown above in [fig. 5].[4] I find, however, that the original and more perfect form of this engine, as employed by the Greeks and ancient Romans, had a sling, made of rope and leather, attached to its arm.[5] ([Fig. 6], following page.)

[4] See also The Crossbow, etc., Chapters LV., LVI., illustrations 193 to 202.

[5] In mediæval times catapults which had not slings cast great stones, but only to a short distance in comparison with the earlier weapons of the same kind that were equipped with slings. I can find no allusions or pictures to show that during this period any engine was used with a sling except the trebuchet, a post-Roman invention. All evidence goes to prove that the secret of making the skein and other important parts of a catapult was in a great measure lost within a couple of centuries after the Romans copied the weapon from their conquered enemies the Greeks, with the result that the trebuchet was introduced for throwing stones.

The catapult was gradually superseded as the art of its construction was neglected, and its efficiency in sieges was therefrom decreased.

The catapults of the fifth and sixth centuries were very inferior to those described by Josephus as being used at the sieges of Jerusalem and Jotapata (A.D. 70, A.D. 67), [p. 37].

Fig. 6.—Sketch plan of a Catapult for slinging Stones its Arm being partly wound down.

Approximate scale: ¼ in. = 1 ft.

The addition of a sling to the arm of a catapult increases its power by at least a third. For example, the catapult described in Chapters LV., LVI., of my book,[6] will throw a round stone 8 lbs. in weight, from 350 to 360 yards, but the same engine with the advantage of a sling to its arm will cast the 8-lb. stone from 450 to 460 yards, and when its skein is twisted to its limit of tension to nearly 500 yards.

[6] The Crossbow, etc.

If the upper end of the arm of a catapult is shaped into a cup to receive the stone, as shown in [fig. 5], p. 11, the arm is, of necessity, large and heavy at this part.

If, on the other hand, the arm is equipped with a sling, as shown in [fig. 6], opposite page, it can be tapered from its butt-end upwards, and is then much lighter and recoils with far more speed than an arm that has an enlarged extremity for holding its missile.

When the arm is fitted with a sling, it is practically lengthened by as much as the length of the sling attached to it, and this, too, without any appreciable increase in its weight.

The longer the arm of a catapult, the longer is its sweep through the air, and thus the farther will it cast its projectile, provided it is not of undue weight.

The difference in this respect is as between the range of a short sling and that of a long one, when both are used by a school-boy for slinging pebbles.

The increase of power conferred by the addition of a sling to the arm of a catapult is surprising.

A small model I constructed for throwing a stone ball, one pound in weight, will attain a distance of 200 yards when used with an arm that has a cup for holding the ball, though when a sling is fitted to the arm the range of the engine is at once increased to 300 yards.

The only historian who distinctly tells us that the catapult of the Greeks and Romans had a sling to its arm, is Ammianus Marcellinus. This author flourished about 380 A.D., and a closer study of his writings, and of those of his contemporaries, led me to carry out experiments with catapults and balistas which I had not contemplated when my work dealing with the projectile engines of the Ancients was published.

Fig. 7.—Catapult (with a Sling). Side view of frame and mechanism.

Scale: ½ in. = 1 ft.

Ammianus writes of the catapult[7]:

‘In the middle of the ropes[8] rises a wooden arm like a chariot pole ... to the top of the arm hangs a sling ... when battle is commenced a round stone is set in the sling ... four soldiers on each side of the engine wind the arm down till it is almost level with the ground ... when the arm is set free it springs up and hurls forth from its sling the stone, which is certain to crush whatever it strikes. This engine was formerly called the “scorpion,” because it has its sting erect,[9] but later ages have given it the name of Onager, or wild ass, for when wild asses are chased they kick the stones behind them.’

[7] Roman History, Book XXIII., Chapter IV.

[8] i.e. in the middle of the twisted skein formed of ropes of sinew or hair.

[9] The upright and tapering arm of a catapult, with the iron pin on its top for the loop of the sling, is here fancifully likened to the erected tail of an angry scorpion with its sting protruding.

[Fig. 7].—Catapult (with a sling), see opposite page.

A. The arm at rest, ready to be wound down by the rope attached to it and also to the wooden roller of the windlass. The stone may be seen in the sling.

The upper end of the pulley rope is hitched by a metal slip-hook ([fig. 6], p. 12) to a ring-bolt secured to the arm just below the sling.

B. The position of the arm when fully wound down by means of the windlass and rope. See also EE, [fig. 8], page 16.

C. The position of the arm at the moment the stone D leaves the sling, which it does at an angle of about 45 degrees.

E. By pulling the cord E the arm B is at once released from the slip-hook and, taking an upward sweep of 90 degrees, returns to its original position at A.

The Sling (open).

[F. Its fixed end which passes through a hole near the top of the arm.

G. The leather pocket for the stone.

H. The loop which is hitched over the iron pin at the top of the arm when the stone is in position in the sling, as shown at A and B, [fig. 7].]

Fig. 8.—Catapult (with a Sling). Surface view of frame and mechanism. Scale: ½ in. = 1 foot. The arm EE is here shown wound down to its full extent. (Compare with B, [fig. 7], page 14.)

The ends of the cross-piece beams are stepped into the side-pieces.

AA. The skein of twisted cord.

BB. The large winding wheels. The skein is stretched between these wheels, its ends passing through the sides of the frame, and then through the wheels and over their cross-bars. ([Fig. 12], p. 19.)

By turning with a long spanner ([fig. 6], p. 12) the squared ends of the spindles DD, the pinion wheels CC rotate the large wheels BB and cause the latter to twist the skein AA, between the halves of which the arm EE is placed.

FF. The wooden roller which winds down the arm EE. ([Fig. 6], p. 12.)

The roller is revolved by four men (two on each side of the engine) who fit long spanners on the squared ends of the iron spindle GG.

This spindle passes through the centre of the roller and through the sides of the frame.

The small cogged wheels, with their checks, which are fitted to the ends of the spindle GG, prevent the roller from reversing as the arm is being wound down. ([Fig. 6], p. 12.)

HH. The hollows in the sides of the frame which receive the lower tenons of the two uprights. Between the tops of these uprights the cross-beam is fixed against which the arm of the catapult strikes when it is released. ([Fig. 6], p. 12.)

KK. The hollows for the lower tenons of the two sloping supports which prevent the uprights, and the cross-beam between them, from giving way when the arm recoils. ([Fig. 6], p. 12.)

Fig. 9.—One of the Pair of Winches of a Catapult. Scale: 1/16 in. = 1 in.

I. Surface view of one of the winches and of the thick iron plate in which the socket of the large winding wheel of the winch revolves.

II. View of a winch (from above) as fitted into one of the sides of the frame of the catapult. One end of the twisted skein may be seen turned round the cross-bar of the large wheel.

III. Side view of the large wheel of a winch.

IV. The cross-bar of one of the large wheels. These pieces fit like wedges into tapering slots cut down the barrels, or inside surfaces, of their respective wheels.

V. Perspective view of the wheels of a winch.

The winches are the vital parts of the catapult as they generate its projectile power.

They are employed to twist tightly the skein of cord between which the butt-end of the arm of the engine is placed.

The cord composing the skein is stretched to and fro across and through the sides of the catapult, and alternately through the insides of the large wheels and over their cross-bars; as shown in [fig. 8], p. 16.

[Fig. 10]. The Iron Slip-hook.

Fig. 10.

This simple contrivance not only pulled down the arm of a catapult but was also the means of setting it free. However great the strain on the slip-hook, it will, if properly shaped, easily effect the release of the arm.

The trajectory of the missile can be regulated by this form of release, as the longer the distance the arm is pulled down the higher the angle at which the projectile is thrown.

On the other hand, the shorter the distance the arm is drawn back, the lower the trajectory of its missile.

The slip-hook will release the arm of the engine at any moment, whether it is fully or only partially wound down by the windlass.

The slip-hook of the large catapult shown in [fig. 6], p. 12, has a handle, i.e. lever, 10 inches long, the point of the hook, which passes through the eye-bolt secured to the arm, being one inch in diameter.

Fig. 11.—A Spring Engine with a Sling attached to its Arm, which cast Two Stones at the Same Time.

From ‘Il Codice Atlantico,’ Leonardo da Vinci. 1445–1520.

Fig. 12.—The Skein of Cord.

A. The skein as first wound over the cross-bars of the large wheels (shown in section) of the winches.

B. The skein with the butt-end of the arm (shown in section) placed between its halves.

C. The skein as it appears when tightly twisted up by the winches. Compare with AA, [fig. 8], p. 16.

Cord of Italian hemp, about ¼ in. thick, is excellent for small catapults. For large ones, horsehair rope, ½ in. thick, is the best and most elastic. Whatever is used, the material of the skein must be thoroughly soaked in neats-foot oil for some days previously, or it is sure to fray and cut under the friction of being very tightly twisted. Oil will also preserve the skein from damp and decay for many years.

HOW TO WORK THE CATAPULT

There is little to write under this heading; as the plans, details of construction and illustrations will, I trust, elucidate its management.

The skein should never remain in a tightly twisted condition, but should be untwisted when the engine is not in use.

Previous to using the catapult its winches should be turned with the long spanner, [fig. 6], p. 12, first the winch on one side of the engine and then the one on the other side of it, and each to exactly the same amount.

Small numerals painted on the surfaces of the large wheels near their edges, will show how much they have been revolved; in this way their rotation can be easily arranged to correspond.

As the skein of cord is being twisted by the very powerful winches, the arm will gradually press with increasing force against the cross-beam between the uprights. The arm should be so tightly pressed against the fender, or cushion of straw, attached to the centre of this beam, that, whether large or small, it cannot be pulled back the least distance by hand.

If the skein of my largest catapult is fully tightened up by the winches, three strong men are unable to draw the arm back with a rope even an inch from the cross-beam, though the windlass has to pull it down from six to seven feet when the engine is made ready for action.

When the skein is as tight as it should be, attach the slip-hook to the ring-bolt in the arm and place the stone in the sling suspended from the top of the arm.

The arm can now be drawn down by means of long spanners fitted to the windlass. Directly the arm is as low as it should be, or as is desired, it should be instantly released by pulling the cord fastened to the lever of the slip-hook.

The least delay in doing this, and the resulting continuation of the immense strain on the arm, may cause it to fracture when it would not otherwise have done so.

The plans I have given are those of my largest engine, which, ponderous as it seems—(it weighs two tons)—is, however, less than half the size of the catapult used by the ancients for throwing stones of from forty to fifty pounds in weight.

As the plans are accurately drawn to scale, the engine can easily be reproduced in a smaller size.

An interesting model can be constructed that has an arm 3 feet in length, and a skein of cord about 4 inches in diameter. It can be worked by one man and will throw a stone, the size of an orange, to a range of 300 yards.

The sling, when suspended with the stone in position, should be one third the length of the arm, as shown in [fig. 7], p. 14.

If the sling is shortened, the ball will be thrown at a high elevation. If the sling is lengthened, the ball will travel at a lower angle and with much more velocity.

PART III
THE BALISTA

Fig. 13.—Balista For Discharging Heavy Arrows or Javelins.
Approximate scale: ½ in. = 1 foot.

This engine is here shown ready for discharge with its bow-string drawn to its full extent by the windlass.

The heavy iron-tipped arrow rests in the shallow wooden trough or groove which travels along the stock.

The trough has a strip of wood, in the form of a keel, fixed beneath it. This keel travels to or fro in a dove-tailed slot cut along the upper surface of the stock for the greater part of its length. (F, [fig. 14], p. 23.)

The arrow is laid in the trough before the bow-string is stretched. (A, B, [fig. 14], p. 23.)

The balista is made ready for use by turning the windlass. The windlass pulls back the sliding trough, and the arrow resting in it, along the stock of the engine, till the bow-string is at its proper tension for discharging the projectile. ([Fig. 13], p. 21.)

As the trough and the arrow are drawn back together, the arrow can be safely laid in position before the engine is prepared for action.

The catch for holding the bow-string, and the trigger for releasing it, are fixed to the solid after-end of the wooden trough. ([Fig. 14], p. 23.)

The two ratchets at the sides of the after-end of the trough travel over and engage, as they pass along, the metal cogs fixed on either side of the stock. ([Fig. 14], p. 23.)[10]

[10] When the bow-string has been released and the arrow discharged, the ratchets are lifted clear of the cogs on the stock of the engine. This allows the trough to be slid forward to its first position as shown in A, B, [Fig. 14]. It is then ready to be drawn back again for the next shot.

By this arrangement the trough can be securely retained, in transit, at any point between the one it started from and the one it attains when drawn back to its full extent by the windlass.

As the lock and trigger of the balista are fixed to the after-end of the sliding trough ([fig. 14], p. 23), it will be realised that the arrow could be discharged at any moment required in warfare, whether the bow-string was fully or only partially stretched.

In this respect the balista differed from the crossbow, which it somewhat resembled, as in a crossbow the bow-string cannot be set free by the trigger at an intermediate point, but only when it is drawn to the lock of the weapon.

It will be seen that the balista derives its power from two arms; each with its separate skein of cord and pair of winches.

These parts of the balista are the same in their action and mechanism as those of the catapult.

[Fig. 14] (Opposite Page).—The Mechanism of the Stock of an Arrow-Throwing Balista.

A. Side view of the stock, with the arrow in the sliding trough before the bow-string is stretched.

B. Surface view of the stock, with the arrow in the sliding trough before the bow-string is stretched.

C. Section of the fore-end of the stock, and of the trough which slides in and along it.

Fig. 14.—The Mechanism of the Stock of an Arrow-throwing Balista.

D. Surface view of the trough, with the trigger and catch for the bow-string.

E. Side view, showing the keel (F) which slides along the slot cut in the surface of the stock as the trough is drawn back by the windlass.

G. Enlarged view of the solid end of the trough. This sketch shows the catch for the bow-string, the trigger which sets it free, the ratchets which engage the cogs on the sides of the stock, and the slot cut in the stock for the dove-tailed keel of the trough to travel in.

* * * * *

Balistas were constructed of different sizes for the various purposes of siege and field warfare. The smallest of these engines was not much larger than a heavy crossbow, though it more than equalled the latter in power and range.

The small balistas were chiefly used for shooting through loopholes and from battlemented walls at an enemy assaulting with scaling ladders and movable towers.

The largest had arms of 3 ft. to 4 ft. in length, and skeins of twisted sinew of 6 in. to 8 in. in diameter.

Judging from models I have made and carefully experimented with; it is certain that the more powerful balistas of the ancients could cast arrows, or rather feathered javelins, of from 5 to 6 lbs. weight, to a range of from 450 to 500 yards.

Fig. 15.—Balista for throwing Stone Balls. Approximate scale: ½ in. = 1 foot.

This engine is here shown with its bow-string only slightly drawn along its stock by the windlass.

It will be seen that this engine is almost identical in construction with the one last described. ([Fig. 13], p. 21.)

The difference is that it propelled a stone ball instead of a large arrow.

The ball was driven along a square wooden trough, one-third of the diameter of the ball being enclosed by the sides of the trough so as to keep the missile in a true direction after the bow-string was released.

The bow-string was in the form of a broad band, with an enlargement at its centre against which the ball rested.

The description given of the mechanism and management of the engine for throwing arrows can be applied to the construction and manipulation of this form of balista, which was also made of large and small dimensions.

Small engines, with arms about 2 ft. in length and skeins of cord about 4 in. in diameter, such as those I have built for experiment, will send a stone ball, 1 lb. in weight, from 300 to 350 yards.

There is little doubt that the large stone-throwing balista of the Greeks and Romans was able to project a circular stone, of 6 to 8 lbs. weight, to a distance of from 450 to 500 yards.[11]

[11] The balls used by the ancients in their catapults and balistas were often formed of heavy pebbles inclosed in baked clay, the reason being that balls made in this way shattered on falling and hence could not be shot back by the engines of the enemy. The balistas for throwing arrows, and those employed for casting stones, were fitted with axles and wheels when constructed for use in field warfare.

Fig. 16.—The Sliding Trough of the Stone-throwing Balista.

A. Surface view, with the stone in position.

B. Side view, with the stone in position.

C. Front view of the stone as it rests in the trough against the enlarged centre of the bow-string.

D. Enlarged view of the solid end of the sliding trough. This sketch shows the ball in position against the bow-string; the catch holding the loop of the bow-string, and the pivoted trigger which, when pulled, releases the catch. One of the pair of ratchets which engage the cogs on the sides of the stock, as the trough is drawn back by the windlass to make ready the engine, is also shown. The trough has a keel to it, and slides to or fro along the stock in the same manner as in the arrow-throwing balista. ([Fig. 13], p. 21.)

Compare with [figs. 13], [14], pp. 21, 23, for further explanation of details.

Fig. 17.—A Siege Balista in the form of an immense Stonebow.

From ‘Il Codice Atlantico,’ Leonardo da Vinci, 1445–1520.

Criticism.—A stonebow of vast size. A and B represent two kinds of lock. In A, the catch of the lock over which the loop of the bow-string was hitched, was released by striking down the knob to be seen below the mallet. In B, the catch was set free by means of a lever. C shows the manner of pulling back the bow-string. By turning the spoked wheels, the screw-worm revolved the screwed bar on which the lock A, travelled. The lock, as may be seen, worked to or fro in a slot along the stock of the engine. In the illustration the bow is fully bent and the man indicated is about to discharge the engine. After this was done, the lock was wound back along the screw-bar and the bow-string was hitched over the catch of the lock preparatory to bending the bow again. Besides being a famous painter, Leonardo was distinguished as an inventor and exact writer on mechanics and hydraulics.

‘No artist before his time ever had such comprehensive talents, such profound skill or so discerning a judgment to explore the depths of every art or science to which he applied himself.’—John Gould, Dictionary of Painters, 1839.

From the above eulogy we may conclude that the drawings of ancient siege engines by Leonardo da Vinci are fairly correct.

PART IV
THE TREBUCHET

This engine was of much more recent invention than the catapult or the balista of the Greeks and Romans. It is said to have been introduced into siege operations by the French in the twelfth century. On the other hand, the catapult and the balista were in use several centuries before the Christian Era. Egidio Colonna gives a fairly accurate description of the trebuchet, and writes of it, about 1280, as though it were the most effective siege weapon of his time.

The projectile force of this weapon was obtained from the gravitation of a heavy weight, and not from twisted cordage as in the catapult and balista.

From about the middle of the twelfth century, the trebuchet in great measure superseded the catapult. This preference for the trebuchet was probably due to the fact that it was able to cast stones of about 300 lbs. in weight, or five or six times as heavy as those which the largest catapults could project.[12]

[12] The catapult had, besides, become an inferior engine to what it was some centuries before the trebuchet was introduced, the art of its construction having been neglected.

The stones thrown by the siege catapults of the time of Josephus would no doubt destroy towers and battlements, as the result of the constant and concentrated bombardment of many engines. One huge stone of from 200 to 300 lbs., as slung from a trebuchet, would, however, shake the strongest defensive masonry.

The trebuchet was essentially an engine for destroying the upper part of the walls of a fortress, so that it might be entered by means of scaling ladders or in other ways. The catapult, by reason of its longer range, was of more service in causing havoc to the people and dwellings inside the defences of a town.

From experiments with models of good size and from other sources, I find that the largest trebuchets—those with arms of about 50 ft. in length and counterpoises of about 20,000 lbs.—were capable of slinging a stone from 200 to 300 lbs. in weight to a distance of 300 yards, a range of 350 yards being, in my opinion, more than these engines were able to attain.[13]

[13] Egidio Colonna tells us that the trebuchet was sometimes made without a counterpoise, and that in such a case the arm of the engine was worked by a number of men pulling together instead of by a heavy weight. I cannot believe this, as however many men pulled at the arm of a trebuchet they could not apply nearly the force that would be conveyed by the gravitation of a heavy weight.

Fig. 18.—The Trebuchet.

The arm is fully wound down and the tackle of the windlass is detached from it. The stone is in the sling and the engine is about to be discharged by pulling the slip-hook off the end of the arm. The slip-hook is similar to the one shown in [fig. 10], p. 18.

N.B.—A Roman soldier is anachronistically shown in this picture. The trebuchet was invented after the time of the Romans.

The trebuchet always had a sling in which to place its missile.

The sling doubled the power of the engine and caused it to throw its projectile twice as far as it would have been able to do without it.

It was the length of the arm, when suitably weighted with its counterpoise, which combined with its sling gave power to the trebuchet. Its arm, when released, swung round with a long easy sweep and with nothing approaching the velocity of the much shorter arm of the catapult.

The weight of a projectile cast by a trebuchet was governed by the weight of its counterpoise. Provided the engine was of sufficient strength and could be manipulated, there was scarcely any limit to its power. Numerous references are to be found in mediæval authors to the practice of throwing dead horses into a besieged town with a view to causing a pestilence therein, and there can be no doubt that trebuchets alone were employed for this purpose.

As a small horse weighs about 10 cwt., we can form some idea of the size of the rocks and balls of stone that trebuchets were capable of slinging.

When we consider that a trebuchet was able to throw a horse over the walls of a town, we can credit the statement of Stella,[14] who writes ‘that the Genoese armament sent against Cyprus in 1376 had among other great engines one which cast stones of 12 cwt.’

[14] Stella flourished at the end of the fourteenth century and beginning of fifteenth. He wrote The Annals of Genoa from 1298–1409. Muratori includes the writings of Stella in his great work, Rerum Italicarum Scriptores, 25 vols., 1723–38.

Villard de Honnecourt[15] describes a trebuchet that had a counterpoise of sand the frame of which was 12 ft. long, 8 ft. broad, and 12 ft. deep. That such machines were of vast size will readily be understood. For instance, twenty-four engines taken by Louis IX. at the evacuation of Damietta in 1249, afforded timber for stockading his entire camp.[16] A trebuchet used at the capture of Acre by the Infidels in 1291, formed a load for a hundred carts.[17] A great engine that cumbered the tower of St. Paul at Orleans and which was dismantled previous to the celebrated defence of the town against the English in 1428–9, furnished twenty-six cartloads of timber.[18]

[15] Villard de Honnecourt, an engineer of the thirteenth century. His album translated and edited by R. Willis, M.A., 1859.

[16] Jean, Sire de Joinville. He went with St. Louis to Damietta. His memoirs, written in 1309, published by F. Michel, 1858.

[17] Abulfeda, 1273–1331. Arab soldier and historian, wrote Annals of the Moslems. Published by Hafnire, 1789–94. Abulfeda was himself in charge of one of the hundred carts.

[18] From an old history of the siege (in manuscript) found in the town hall of Orleans and printed by Saturnin Holot, a bookseller of that city, 1576.

All kinds of articles besides horses, men, stones and bombs were at times thrown from trebuchets. Vassāf[19] records ‘that when the garrison of Delhi refused to open the gates to Ala’uddin Khilji in 1296, he loaded his engines with bags of gold and shot them into the fortress, a measure which put an end to the opposition.’

[19] Persian historian, wrote at end of thirteenth and beginning of fourteenth century. The preface to his history is dated 1288, and the history itself is carried down to 1312.

[Figs. 18], [20], pp. 28, 32, explain the construction and working of a trebuchet.

Fig. 19.—Casting a dead Horse into a besieged Town by means of a Trebuchet.

From ‘Il Codice Atlantico,’ Leonardo da Vinci, 1445–1520.

PART V
HISTORICAL NOTES ON ANCIENT AND MEDIÆVAL SIEGE ENGINES AND THEIR EFFECTS IN WARFARE

It is evident that a history of ancient siege engines cannot be created de novo. All that can be done is to quote with running criticism what has already been written about them.

The first mention of balistas and catapults is to be found in the Old Testament, two allusions to these weapons being made therein.

The references are:

2 Chronicles xxvi. 15, ‘And he[20] made in Jerusalem engines, invented by cunning men, to be on the towers and upon the bulwarks, to shoot arrows and great stones withal.’

[20] Uzziah.

Ezekiel xxvi. 9, ‘And he shall set engines of war against thy walls.’

Though the latter extract is not so positive in its wording as the one first given, it undoubtedly refers to engines that cast either stones or arrows against the walls, especially as the prophet previously alludes to other means of assault.

One of the most authentic descriptions of the use of great missive engines is to be found in the account by Plutarch of the siege of Syracuse by the Romans, 214–212 B.C.

Cæsar in his Commentaries on the Gallic and Civil wars, B.C. 58–50, frequently mentions the engines which accompanied him in his expeditions.

The balistas on wheels were harnessed to mules and called carro-balistas.

The carro-balista discharged its heavy arrow over the head of the animal to which the shafts of the engine were attached. Among the ancients these carro-balistas acted as field artillery and one is plainly shown in use on Trajan’s Column.

According to Vegetius, every cohort was equipped with one catapult and every century with one carro-balista; eleven soldiers being required to work the latter engine.

Fig. 20.—The Action of the Trebuchet.

A. The arm pulled down and secured by the slip-hook previous to unhooking the rope of the windlass. B. The arm released from the slip-hook and casting the stone out of its sling. C. The arm at the end of its upward sweep.

Sixty carro-balistas accompanied, therefore, besides ten catapults, a legion. The catapults were drawn along with the army on great carts yoked to oxen.

In the battles and sieges sculptured on Trajan’s Column there are several figures of balistas and catapults. This splendid monument was erected in Rome, 105–113, to commemorate the victories of Trajan over the Dacians, and constitutes a pictorial record in carved stone containing some 2,500 figures of men and horses.