Saturday, February 10, 2007

Military Pyrotechnics of Former Days

Posted on Monday, June 21, 2004.
The story of Greek fire, the “wonderful combustible.”
Originally from Harper's New Monthly Magazine, vol. 39, iss. 229, June 1869. By Jacob Abbott.

The predecessor of gunpowder in the history of war has always been considered to be a wonderful combustible known as Greek Fire, of which the most marvelous accounts have been circulating among mankind during the past two or three centuries. This Greek fire has been supposed to be a combustible possessed of most astonishing properties. It was capable of being thrown so as to envelop whole buildings, and even to overwhelm and destroy complete battalions on the field. Water would not extinguish it, but only made it burn the brighter. Nothing would put it out but drenching it with vinegar, or covering it with sand. Its composition, it was supposed, was lost in the fourteenth century, and had never been recovered. The fact that the art was lost was inferred from the fact that no substance possessing the wonderful properties attributed to the Greek fire can be produced at the present day.
It is somewhat difficult at the present day to obtain exact information in respect either to the composition of this substance, the construction of the engines or other apparatus employed in projecting it, or to the effects which it really produced. In respect to the machinery, and the form of the missiles, we must remember that there were no pictorial papers in those days, and no photography to preserve for future generations the exact realities of form and structure connected with the pursuits and usages of men. And in regard to the other points, relating to the properties of the substance, and the actual effects produced, far less reliance can be placed on the statements of even intelligent, cultivated, and careful men than might be supposed at the present day. For the line of demarcation between the natural and the supernatural—between what is and what is not scientifically possible—was then very vague and obscure, even in the highest minds. Ideas of the natural and supernatural were mingled and confused, or rather the supernatural was regarded as a legitimate realm of the natural, so that no tale could be so marvelous as to seem incredible, even to a grave and cautious historian. At the present day the recitals of excited or terrified witnesses, whose imaginations or whose fears lead them entirely to misconceive what they see, are at once corrected by that general knowledge of the relations of cause and effect which now prevails so extensively among all well-informed men that the bounds of the possible can not be very easily transgressed in narrations generally received. But it was not so in those early times.
In respect to the apparatus by means of which the compound of combustibles known as Greek fire was projected into the enemy's works, some representations have come down to us, though only from comparatively modern times. The use of such means of attacking the vessels or fortresses of the enemy seems to have been resorted to in very early times, since allusions to them occur not unfrequently in the works of writers who lived and wrote several centuries before Christ. Indeed, one of the recipes for making such compositions, as they were employed in those early days, is still extant. It is as follows:
“To make an unquenchable fire take pitch, sulphur, tow, manna, resin, and the scrapings or saw-dust of resinous wood, such as torches are made from. Mix these substances well, then light the mass and throw it against whatever you wish to set on fire.”
It is obvious that such a mixture as this would form an exceedingly combustible compound; but it could not possess any of those marvelous qualities which were attributed to the Greek fire. It could not burn under water, for example.
The use of combustibles of this character seems to have been first resorted to in the countries lying about the eastern shores of the Mediterranean—unless indeed the Chinese, and some of the other Oriental nations, anticipated the Europeans in this, as they have done in respect to many other important discoveries. The reason why the use of such a mode of warfare appeared first in these Oriental countries is supposed to be because in that region are found natural deposits of certain combustible fluids, such as naphtha, and other vegetable oils, which were admirably adapted to this use. At any rate the employment of such substances appears first conspicuously in history in the time of the Greek empire. A great many recipes are extant describing the different kinds of composition employed. They all, however, consist of a mixture of simple combustibles, depending for flagration on access to the air.
These substances were placed in barrels, balls, or other receptacles, and thrown by means of various mechanical contrivances known in those days into the works of the enemy. The Slinging Engine was constructed to throw a barrel of the combustible compound by means of a gigantic sling, seen in the engraving above as thrown open from the end of the beam, after the projection of the barrel. The beam was drawn back by means of the rope wound round the capstan, shown behind and below it. Its elasticity, after being thus brought into a state of great tension, was then suddenly released, when the end of the beam, carrying the barrel of combustibles, previously set on fire, was thrown violently forward and the barrel hurled from the sling, all in flames, into the works of the enemy. A battering engine, the design and operation of which is obvious, stands by the side of the sling.
The above engraving, copied from an illumination in a Latin manuscript of the thirteenth century, gives a representation of the mode of employing the Greek fire in naval warfare. The craft here represented seems to be in some sense the prototype of the modern bomb-proof, ram, and fire-ship, all in one. But although this drawing is taken from an ancient work, no absolute reliance can be placed on the details of the construction as represented in it, inasmuch as such drawings were made in those days for purposes of embellishment, and not for instruction, and so only a general resemblance to the natural object, sufficient to suggest its character and use to the mind of the reader, was all that was usually aimed for. It was, in other words, the ideal and not the actual presentation which the artist had in mind.
All that can be certainly inferred, then, from such an illustration is that a species of vessel was made use of in those times covered with a roof sufficient to protect the navigators from spears and arrows, and provided with a pointed prow to act as a ram, and projecting beams bearing barrels charged with materials for producing the Greek fire. Another form of vessel is given in an ancient manuscript, differing materially from the last. In this the barrel containing the fire is suspended from a species of crane, by means of which it could be swung over the decks of an enemy's ship when in close quarters. In this, as well as in the other case, all that we can infer from the drawing is the general nature and design of the contrivance, and of the principle on which it operated. The true proportions of the parts and the details of the construction were purposely disregarded in illustrations of this kind.
Observe in the engraving the extra barrel of combustibles ready upon the deck, and the circular watch-box on the top of the mast, where a look-out-man could be stationed, under protection from the spears and arrows of the enemy, and yet at the same time in a position to observe every thing through the slits in the box, and so to direct the helmsman in guiding the vessel. Weapons of the character of boarding-pikes are placed, ready for use, at the stern.
The damaging and destructive effects of the Greek fire were not confined to its power of setting the enemy's works on fire. It contained substances which emitted fumes of a horribly offensive, poisonous, and destructive character. It was necessary on this account that the wind should be in the right quarter, that is, blowing from the assailants toward the enemy, whenever it was employed. Sometimes the receptacle containing the composition was placed upon the end of a long spar attached to a car, which was to be propelled by hand. The soldiers would pile up a great quantity of wood before the gate of the castle or strong-hold attacked. This car would then be driven by soldiers stationed behind it, where they were protected by an inclined shield from the assaults of the enemy. The shield is perforated with openings, to enable those within could not be sufficient in quantity to burn for a long time.
The marvelous tales which have been told in respect to the power of the Greek fire to burn under water have a certain foundation in the fact that, in the times when this agency was employed in war, the method of using it was by packing the materials in a spherical receptacle, in such a manner that when thrown into the water the missile could go down to a certain distance without being entirely extinguished, so that on rising again to the surface the flames would break out anew, ready to set fire to any combustible object that they might encounter. The engraving below, copied from one of the ancient illustrations, gives a general idea of this operation. The balls thrown from a height into the water would of course sink below the surface, until brought back again by their buoyancy; and there would be no great difficulty in so storing so very combustible a material as that it should retain the fire during this brief interval.
The transition from the manufacture of Greek fire to that of gunpowder in war, it is now found, was not the result of any sudden discovery, but grew gradually out of the incidental introduction of saltpetre among the combustible substances, which was found in some mysterious way greatly to increase the violence of the combustion. Saltpetre is a substance which is found abundantly in a natural state in the countries where Greek fire was most used. The mode of its operation in changing combustion into explosion was not probably at first comprehended, as the science of chemistry was then practically unknown. It is now, however, understood that the result is due to the saltpetre's furnishing a supply of oxygen to the combustibles, and thus making them independent of the air in respect to their burning. It furnishes the supply, too, in such a way, to every particle of the combustible, by means of the fine comminution and intimate commixture of the materials, as to present to every portion of the combustible a portion of oxygen close at hand, and thus increases enormously the rapidity and violence of the action.
There is another important thing to be borne in mind, which is, that a mixture of combustibles with saltpetre, by containing within itself the supply of oxygen necessary for the combustion, and thus making the process independent of the external air, allows of the inclosing of the materials in strong and tight receptacles, so that the gases produced by the combustion may be confined, and so made to exert their vast expansive force—enormously increased by the great heat developed — upon the walls of the receptacle which confines them.
The mode in which saltpetre thus operated in promoting rapidity of combustion was not probably at all understood in those days. It was observed, however, by many persons and in many different countries, as a matter of fact, that the admixture of saltpetre with their other pyrotechnic materials greatly increased the effect, until finally an explosive power was developed sufficient for the projection of missiles from the mouths of open tubes, and then artillery began to appear on the field of battle.
Thus the art of producing gunpowder for the purposes of war seems to have been a growth rather than an invention; and so it is not at all surprising that the origin of it has been attributed to many different men of many different nations. It is as impossible, as a distinguished French writer has said, to answer the question who invented gunpowder as to say who invented the boat.
This is Military Pyrotechnics of Former Days, an essay and a subject, originally from June 1869, published Monday, June 21, 2004. It is part of War, which is part of Harper's Archive, which is part of Harpers.org.

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