Nature's Teachings

CHAPTER VIII.
CONCEALMENT.—DISGUISE.—THE TRENCH.—POWER OF GRAVITY.—MISCELLANEA

Concealment needed in Modern Warfare.—Concealment by Covering.—Masking Guns.—Birnam Wood.—The Reduvius.—The Cuckoo-spit and the Spider-crab.—Concealment by Disguise.—Stratagem of the Barea.—Complete Deception.—Larva of Geometra.—The Leaf-insect.—The Luppet-moth.—The Ptarmigan and the Ermine.—Principle of the Trench.—The Hunter’s “Skärm.”—The Wax-moth or Galleria-moth, and its Tunnel.—Fate of a Collection.—The Termites and the Travelling Ants of South America.—The Power of Gravity.—The Battering-ram and its Force.—Miscellanea.—War by Suffocation.—The Stink-pot.—The Chili-plant.—The Sulphur-room.—The Bombardier-beetle.—The Bullet-making Machine and the Silkworm.

Concealment

WE will first take Concealment by means of Covering.

If History repeats herself, so does Warfare. I have already shown the repetition of History in the Fortress—I shall now show it in the Field.

In former days, when arms of precision were not invented, concealment was not needed. No soldier ever was visited with a dream so wild as that of taking definite aim at the enemy, and reserving the fire until the aim was certain. I have in my collection several of the French and English muskets used about the time of Waterloo, and, though a fair rifle-shot, would not engage to hit a haystack with either of them at a distance of a hundred yards. With the Snider or Martini-Henry in the hands of a skilful adversary, he would be a bold man who would offer himself for a target at a thousand yards. Indeed, if the first shot happened to miss, the marksman would be tolerably sure to notice the failure, and to correct his aim with fatal certainty.

In those days, therefore, concealment was rather ridiculed than praised, the power of the new arm not being as yet appreciated. I well recollect, in the earliest days of the Volunteer movement, hearing a Volunteer captain declare, amid the cheers of his company, that “he had never sneaked behind a tree in all his life, and was not going to begin now.”

In the present day, the power of the missile has been developed with such astounding rapidity, that to be exposed to the fire of rifles or cannon is almost certain death. Indeed, the only safety of the defence lay in the fact that the smoke soon rendered very accurate shooting impossible at long ranges, and that at short ranges, if a man got a bullet through his body, it mattered little to him whether the missile were a spherical musket-ball or a conical rifle-bullet.

Just, then, as forts have latterly sunk into the earth for the purpose of strength, so have our modern soldiers found that the true principle of modern warfare is never to lose sight of the enemy, and never to allow the enemy to see yourself or the disposal of your troops.

Everything must be revealed to the commander-in-chief, everything must be concealed from the enemy.

In the late Franco-German war the principle of concealment was largely used, and when cannon were brought into the field by the Germans for the purpose of attacking fortresses, they were always hidden under branches of trees, so that the enemy should not distinguish them from the ordinary features of the country, and that the sparkle of the sunbeams upon them might not be seen.

It would be almost superfluous to remind the reader of Malcolm’s stratagem when besieging Dunsinane Castle:—

 
“Let every soldier hew him down a bough,
And bear’t before him; thereby shall we shadow
The numbers of our host, and make discovery
Err in report of us.”
 

Precisely similar modes of concealment are to be found in the animal world.

There is a certain insect belonging to the Heteroptera, and scientifically named Reduvius personatus. I am not aware whether it has any popular name. It is insectivorous, and ought to be welcomed in houses, as it is particularly fond of the too common bed-bug. So carnivorous are these insects that one of the Reduviidæ killed and sucked a companion of her own sex, her own mate, and, after only a few days’ fast, her own young, and then sucked her own eggs.

During its larval and pupal stages of existence, the Reduvius covers its body and limbs with dust and any other refuse which it can find. In this manner it disguises its form so completely that it scarcely looks like an insect. Occasionally it seems to be dissatisfied with its coat of dust, throws it off, and sets to work at a new one.

One of these creatures, as it appears when covered with its dusty coating, is seen in the upper left-hand corner of the illustration. It is slightly magnified.

Below the Reduvius is the common Cuckoo-spit (Aphrophora spumaria), whose frothy masses are so plentiful in our hedgerows and gardens.

If one of these masses be carefully opened, there will be found in it a little green creature with small, round, dot-like eyes. This is either the larval or pupal state of the Frog-hopper, as the insect is called in its perfect state, from its habit of taking long and sudden leaps when alarmed.

I well remember my delight when, as a child, I set to work at examining these froth-masses, and succeeded in tracing the insect through all its changes. The froth is derived from the sap of the tree, which is sucked through the proboscis, passed through the digestive organs, and then ejected in a succession of little bubbles. After awhile a little drop of clear liquid is seen to collect at the bottom of the froth, to increase, and then to fall, when another immediately begins to be formed. One species of Cuckoo-spit, which inhabits Madagascar, acts almost like a siphon on the tree, and pours out large quantities of clear water during the hottest part of the day.

Within this froth-mass the insect lies concealed, and, though utterly helpless, is safe from most of the enemies that would attack it if it were left exposed.

Beneath the Cuckoo-spit is the common Spider-crab, sometimes called the Thornback-crab, from the numerous spines with which its body is covered. Its scientific name is Maia squinado.

When the Spider-crab attains to a tolerable size, its rough surface forms attachment for various marine beings, chiefly those belonging to the zoophytes. In some cases these zoophytes grow to such a size that the Crab is completely covered by them, and its original shape effectually concealed. When one of these creatures is seen in a living state it presents the curious spectacle of a large bunch of zoophytes and corallines moving about from place to place without any perceptible limbs, the whole of the surface of the Crab being covered with extraneous growths.

Disguise

Next comes concealment by means of Disguise.

On the right hand of the accompanying illustration is shown a singular mode of concealment adopted by the Barea, a warlike and predatorial tribe of Abyssinia. When Mr. Mansfield Parkyns was resident in Abyssinia he fell in with the Barea, through whose country he had to pass.

“Scarcely had we passed the brook of Mai-Chena when one of our men, a hunter, declared that he saw the slaves. Being at that time inexperienced in such matters, I could see nothing suspicious. He then pointed out to me a dead tree standing on an eminence at a distance of several hundred yards, and charred black by last year’s fire.” Here I must explain that in Abyssinia, as in several other parts of the world, the ground is annually, cleared of its superabundant vegetation by setting fire to it, and allowing the flames to burn themselves out.

“However, all I saw was a charred stump of a tree and a few blackened logs or stones lying at its feet. The hunter declared that neither the tree nor the stones were there the last time we passed, and that they were simply naked Barea, who had placed themselves in that position to observe us, having no doubt seen us for some time, and prepared themselves.

“I could scarcely believe it possible they could be so motionless, and determined to explore a little. The rest of the party advised me to continue quietly in the road, as it was possible that, from our presenting a rather formidable appearance, we should pass unmolested; but so confident was I of his mistake, that, telling the rest to go on slowly, as if nothing had been observed, I dropped into the long grass and stalked up towards them.”

“A shot from my rifle at a long distance (I did not venture too close) acted on the trees and stones as powerfully as the fiddle of Orpheus, but with the contrary effect; for the tree disappeared, and the stones and logs, instead of running after me, ran in the opposite direction.”

“I never was more astonished in my life, for so complete was the deception that even up to the time I fired I could have declared the objects before me were vegetable or mineral—anything, indeed, but animal. The fact was that the cunning rascals who represented stones were lying flat, with their little round shields placed before them as screens.”

This stratagem is shown on the right hand of the illustration.

On the left are a few of the innumerable instances in Nature where Concealment is obtained by imitation.

The three examples which are here given are familiar to all entomologists.

The upper figure represents two of the Geometra or Looper Caterpillars, as they appear when at rest, and affixed to a twig. This appears to be a singular attitude of rest, but it is one in which they delight, and in which they remain for hours together, the claspers at the end of the body tightly grasping the branch, and the whole body held out so straight and motionless that it is hardly possible to believe that a veritable twig is not before the eye. The colour is that of the twig, and the different segments of the body look exactly like the little irregularities and projections of a young twig.

I have more than once seen a novice in entomology unable to distinguish these larvæ, even when the branch was pointed out, and there were several upon it.

Just below the Loopers, and on the left hand of the illustration, is shown the well-known Leaf-insect (Phyllium). These strange beings have the elytra and the flattened appendages of the legs so exactly like leaves that the most experienced eye can scarcely distinguish them from the leaves among which they are placed. Even when they have been on a small plant, such as a myrtle in a flower-pot, I have had the greatest difficulty in finding them, and have seen people examine the plant, and then go away declaring that no insects were on it.

On the right hand, and just below the looper caterpillar, is the common Lappet-moth of this country, shown in its position of rest.

When it assumes this attitude, it looks exactly like a withered leaf, the resemblance extending not only to the form, but the colour. All entomologists are familiar with many similar examples in insect life. The common Tortoise-shell Butterfly, for example, has a way of settling on patches of red soil, with which it harmonizes so well that it can hardly be seen. The various moths, also, are in the habit of resting on tree-bark, palings, and other objects, to which they instinctively know that they assimilate in hue. Many a beginner in entomology will pass a wooden fence or a wall, and not see an insect on either, while an adept will follow him and take twenty or thirty good specimens.

The last figure in the illustration represents a Ptarmigan (Lagopus vulgaris) in its winter dress. These birds have two differently coloured dresses, one for summer and the other for winter, and both adapted for concealment by imitation. In the former dress it is mottled with various shades of blackish brown, yellow, and white. As the bird is in the habit of settling among the grey lichen-covered stones on the sides of rocky hills, these colours harmonize so exactly with them that a Ptarmigan may almost be trodden upon before it is perceived.

In the winter, when the snow covers the whole country with one uniform sheet of white, except where the wind blows the snow aside, and exposes the underlying stones, the Ptarmigan assumes a different plumage, being almost entirely white, except a black streak over the eye, and the outer feathers of the tail, which are also black. Thus the bird becomes almost indistinguishable from a snow-covered stone, especially as it has a habit of squatting motionless and silent when it takes alarm.

The reader may, perhaps, remember that the common Stoat also has a summer and winter dress. The ordinary colour is rich reddish brown above, and white beneath, with a black tip to the tail. In the severe winters of Northern Europe the Stoat exchanges his ruddy coat for one of pure white, and is then known by the name of Ermine. It is remarkable that in the winter dress both of the Ptarmigan and Stoat the tail is black, while the rest of the coat is white.

The Trench

We now come to a third mode of concealment in war, namely, that which is obtained by means of Trenches or Pits.

Even in hunting the pit or partial trench is largely used. In Southern Africa the hunter often employs such a trench, called technically a “Skärm.” It is very simple in idea, and easily made, being based on the principle that lions, elephants, &c., look for their assailants on the level of the earth, and seldom, if ever, look above or below it. Accordingly the hunter, having marked some pool or lake whereunto the wild animals resort at night to quench their thirst, chooses a convenient spot, and there digs a trench some seven feet in length and four deep, and covers it in with stout tree-branches and logs of various size. The whole is roofed in with sods, and the only entrance is at one end.

Here the hunter sits and waits, and, as his ear is on a level with the surface of the ground, he can hear at a considerable distance sounds which would have escaped him had he been erect.

Waiting for a favourable opportunity, as the various beasts come to drink, the hunter chooses one, takes careful aim, and fires one of his heaviest guns. It is but seldom that the rest of the animals charge in the direction of the Skärm, but even if they do, the hunter is quite safe under the shelter of his strong roof, which is able to resist even the heavy tread of an elephant.

In modern warfare, and especially during sieges, the trench is largely used, and is constructed on the most scientific principles, so as to shelter the assailants, while enabling them to proceed nearer and nearer to the fortress. A portion of one of these trenches is shown in the right hand of the illustration.

On the opposite side of the same illustration is shown the same principle as carried out in Nature.

There is a certain little insect, called the Wax-moth, or Galleria-moth (Galleria alvearia), which, although quite harmless in its perfect form, is in its larval state extremely injurious to beehives.

The mother moth contrives, aided by her tiny form and sombre colouring, to slip past the sentries at the mouth of the hive, and to lay her eggs among the combs. This done, she dies, but the evil of her visit lives after her.

Each of the eggs is hatched into a little caterpillar, having a soft grey body, but a hard, horny head of a black-brown colour. As soon as they are hatched they begin to feed, eating not only the waxen combs, but the honey and the bee-bread which were intended for the support of the legitimate inhabitants.

The reader may ask why the bees do not destroy this marauder on their premises. They would be only too glad to do so, but they cannot touch it. As it eats its way along, it constructs a strong silken tube, within which it lives, and which it gradually lengthens. This tube or gallery is exceedingly tough, and perfectly capable of resisting the bee’s sting. Moreover, the caterpillar traverses its tube with such rapidity that the bee has no chance of knowing whereabouts the caterpillar may be when it makes its attack. When it feeds it only protrudes its armed head, the horny covering of which is an effectual protection against the sting.

When these creatures fairly get hold of a hive, the damage which they do is terrible, the whole of the combs being enveloped in the ever-increasing labyrinth of tubes. Even the bees themselves fall victims to the Galleria-moth, for the silken tunnels are driven through and through the combs, enveloping the broad cells as in the meshes of a net. Consequently, when the young bees are developed, they cannot escape from their cells, and perish miserably.

Nor do these tiresome insects confine themselves to hives; but they have an extraordinary facility for discovering bee-combs after they are removed from the hive. Some years ago I was making a collection of various insect habitations, and had brought together a carefully selected set of combs, showing the internal structure of the hive, and the different cells which are inhabited by the worker, the drone, and the queen bee.

One day, when about to arrange the collection in a glass case, I found that the whole of the combs had been destroyed by the Wax-moth. Scarcely a square inch of comb remained, and the contents of the box were little more than a congeries of Wax-moth galleries. Even the Wasp and Hornet nests which had been placed in the same box had been attacked, and, although they had not been so utterly destroyed as the waxen cells, they had been sufficiently injured to render them unfit for exhibition.

Many other insects work on the same principle. Certain Termites, for example, construct tunnels of clay, in order to conceal them on their travels, and have the art, even in the hottest and driest weather, of mixing their clay with some liquid which renders it, when dry, nearly as hard as stone. Indeed, there have been instances where the Termites have attacked the wooden beams of houses, and literally transformed them into beams of stone.

Then there are many Ants, notably several species of South America, which cover their approach by tunnels, and never venture into the open air.

Gravity as a Propulsive Agent

The two figures on the accompanying illustration will almost speak for themselves.

We have already seen how the same force of gravitation which causes the avalanche to thunder down the precipice may be utilised as a means of projecting missiles in time of war. When, however, the stones or beams were once sent on their destructive mission, they were out of the control of those who launched them. We now come to a modification of the force of Gravity, by which the missile, if we may so term it, is kept under control, its power increased or diminished at will, and its point of attack shifted according to the requirements of the moment.

Before the invention of artillery, the Battering-ram was by far the most formidable engine that could be brought against a fortified place. The principle of the Battering-ram was simple enough. A long and heavy beam, generally the trunk of a tree, was suspended by ropes at the centre of gravity, so that it could be swung backwards and forwards. Although a simple beam was an effective weapon, its value was much enhanced by loading the thickest end with a heavy mass of metal, usually iron, and, when there was time for adornment, roughly modelled into the form of a ram’s head.

Generally the Battering-ram was mounted on an elevated platform, and the soldiers who worked it protected by a roof, which was called by the name of Testudo, or Tortoise. The force of this weapon was tremendous, and no wall, however strong, could resist it. Sometimes the beam was considerably more than a hundred feet in length, being composed of several pieces bolted and banded together with iron.

It may easily be imagined that such a weapon as this must have been a most terrible one, and, indeed, the whole success of the siege practically depended upon it. The assailants did their best to bring the Battering-ram into position under the walls, and the besieged did their best either to keep it away, or to neutralise its effects by catching it with nooses, dropping large stones upon it so as to break or dismount it, or, if they could not succeed in either of these attempts, they deadened the force of its blows as well as they could by interposing large sacks of wool between the wall and the head of the ram.

Considering the style of architecture which was then used in fortification, namely, a combination of height with thickness, the force of the Battering-ram would be even greater than that of artillery. The regular and rhythmical swing of the ram would soon communicate a vibratory motion to the wall, which would of itself tend to disintegrate the whole structure, while the blows of the iron head beneath broke away the stones, and rendered the downfall of the fort a mere matter of time.

The reader need hardly be reminded that the Battering-ram was so called because its mode of attack was practically the same as that of the animal from which it took its title.

Miscellanea

By slow degrees, mankind, as they advance in civilisation, have robbed warfare of many horrors. Non-combatants, for example, are now left unharmed. Poisoned weapons have, by common consent, been abolished, and so have those instruments of warfare which, though they do not simply poison the blood by means of bodily wounds, do so by means of noxious vapours poured into the lungs.

It is sometimes rather unfortunate when civilisation and semi-barbarism meet in battle; the former respecting the customs of honourable warfare, and the latter ignoring them. For example, in olden times, one of the most potent weapons in naval combat was the “stink-pot”—i.e. a vessel filled with sulphur and other ingredients, and emitting a smoke which was death when inhaled. Among the American Indians the well-known Chili-plant was much used for this purpose, the very first breath that was taken of the thin and almost invisible smoke causing the throat to contract as if clutched by a strong hand. If then any enemies had taken refuge in a cave, or were suspected of having done so, a fire was lighted at the entrance, a quantity of chilis thrown on it, and the rest left to time. No being could endure that smoke and live, and they must either stay in the cave and die, or come out and deliver themselves up to their foes. The former was the better part to take, as suffocation, however slow, is only an affair of a few minutes, while death by torture is prolonged through hours.

In the late Chinese war the stink-pot was extensively used, and our sailors took it in very bad part that the enemy should be allowed to employ such weapons, and they should be debarred from using them.

Whether this principle is still retained in the defence of fortresses I do not know. I recollect, however, some twenty years ago, going over a fortress in which suffocation was employed as a means of defence. A long gallery was so placed that the assailants were tolerably sure to force their way into it, thinking that it led to the interior of the fort.

It was, however, nothing but a trap, for it had no exit. As soon as a number of the assailants had poured into this trap, their exit was suddenly cut off by machinery provided for the purpose, and at the same time a quantity of sulphur and lighted charcoal was shot into the gallery from above, and the aperture instantly closed. It would be absolutely impossible that any one who had been enclosed in that terrible chamber should escape with life, for the first breath of that deadly vapour would render the strongest man insensible.

Nature, as usual, has anticipated Art even in this particular.

In several parts of England, and especially along the shores of the Thames towards Gravesend, a little beetle is to be found under the flat stones of the river bank. Its scientific name is Brachinus crepitans. When this insect is alarmed, it has the power of ejecting a peculiar liquid, which, when it comes in contact with the atmosphere, bursts into a sort of pale blue-green flame, followed by a kind of smoke. Sometimes, when a tolerably large stone is lifted, the little explosions will go popping about in a most curious manner. Indeed, they carry reminiscences of school days, when it was a joy to distribute single grains of coarse gunpowder on the bars of the grate, and watch them melt, take fire, explode, and send forth little clouds of smoke. The insect is popularly called the Bombardier-beetle. Whether or not this capability be given as a means of defence I cannot say, but it assuredly answers that purpose.

There are several of the voracious Carabidæ, or Ground-beetles, which would be very glad to make a meal of the Brachinus. When, however, the Bombardier-beetle finds itself on the point of being overtaken, it elevates the abdomen with a peculiar gesture, and ejects the liquid. The effect on the pursuer is remarkable. It seems overwhelmed and stupefied by the sudden attack, moves about for awhile as if blinded, and, by the time that it has recovered its sense, the Bombardier-beetle is out of sight.

In some of the hotter parts of the world there are several species of Bombardier-beetles which attain considerable size, and their discharge is powerful enough to discolour the skin of the human hand.

I have felt some little difficulty in classifying the curious invention which will now be described, but, as it is used for the purpose of making bullets, I have placed it in the category of War.

In the days of “Brown Bess,” as the old musket used to be called, precision of aim was not required, for no commander dreamt of opening fire until the enemy were at comparatively close quarters. In those days the bullets were spherical, and cast in moulds. After a time, when the Enfield rifle displaced the musket, and did double the execution at three times its range, bullets were still cast, though their shape was altered, and they took a sugar-loaf form instead of being spherical.

The rifle-testing machine at Woolwich, however, soon showed that at long ranges a cast bullet was nearly useless, one part being always lighter than another, and air-bubbles often taking the place of lead. After being cast, therefore, the bullets were placed in a “swedge,” or “swage,” i.e. a machine by which the lead was forcibly compressed until it was of a tolerably uniform density. Even this process, however, did not insure absolute exactness, and then a machine was invented by means of which the process of casting was superseded, and the bullets were pinched or squeezed, so to speak, out of cold lead.

On the right hand of the illustration is a plan of the ingenious apparatus by which the lead is supplied to the machine which actually forms the bullets. The sketch is not meant as a drawing of the actual machine, but is merely intended to show the principle.

The chief parts in this machine are a hollow cylinder, a piston, and a delivery tube. The cylinder is shown at A, and when used, is filled with melted lead. The piston, B, is then forced upwards by hydraulic pressure, driving the lead through the delivery tube. As it issues into the air it hardens, and thus forms a solid rod of lead, C. This rod is then passed into the next machine, where it is cut into regular lengths, and these pieces are then placed in moulds, and forced into form by enormous pressure. Were it not for this ingenious machinery, the wonderful scores which are now made at long distances would be impossible.

Now let us compare Art with Nature, as seen on the left hand of the illustration, which is a chart or plan of the spinning apparatus of the Silkworm.

When I first saw the bullet-making machine at work, I at once perceived that it was nothing more than a repetition in metal of the beautiful mechanism which I had so often admired in this insect. In order to show the close analogies of the two objects, I have marked them with similar letters.

A represents the upper part of the reservoir or vessel which contains the silk in a liquid state, B B are the muscles which contract the reservoir and force the liquid matter out. It will be seen that both these vessels terminate in a delivery tube, identical in office with that of the bullet-making machine. As soon as the liquid silk passes into the air it is hardened, and is formed into a silken rod, C, just as is the lead in the machine. The only difference between the two, if it can be called a difference, is, that in the silkworm the rod is double, whereas in the machine it is single. The principle, however, is identical in both cases. The webs of spiders, and the threads by which so many caterpillars suspend themselves, and with which they make their nests, are all formed on the same design, namely, a reservoir containing a liquid which is squeezed through a tube, and hardens when it comes in contact with the air.