Chap. 2.]

And Mexicans.

255

monuments of Egypt (those of Beni Hassan) the latter are represented in the remote age of Osirtasen, 1700 B. C. which to a superficial observer might lead to the supposition that the former were then unknown; but a close examination of the sculptures shows the fallacy of such a conclusion, since blowing tubes are also figured long after the reign of Thothmes in whose time bellows were certainly common. Again, on the last day of the feast of Tabernacles, the Jews were allowed by rabbinical precepts to light one fire from another, but not to strike new fire from stone or metal, nor to quench it, although to save their goods, "nor to blow it with bellowes, but with a reede." Now a stranger, having an imperfect knowledge of Jewish customs, upon witnessing fires thus blown would, in some parts of the world, be very apt to conclude that they had no bellows. And again, if we had not a proof that our domestic bellows was known to the Romans, we might have inferred from Pliny's account of statuaries and painters representing individuals blowing fires with their mouths, that artificial instruments for the purpose were then unknown.

Enough may be gathered from early writers on America to account for bellows not being employed in those operations in which they would seem to have been most required, viz: in smelting of metals. According to Acosta, some ores could not be reduced by bellows, but only by air furnaces. Garcilasso, in the last chapter of the eighth book of his Commentaries, makes the same remark. In smelting the silver ore of Potosi, he says the Indians used neither bellows nor blowing tubes, but a natural wind, which, in their opinion, was the best; they therefore fused the ore in small furnaces placed on the hills in the night time, whenever the wind was sufficient for the purpose; and it was a pleasant sight, he observes, "to behold eight, ten, or twelve thousand of those fires at the same time, ranged in order upon the sides of the mountains." The Spaniards suspecting that the metal, when thus diffused among a great number of hands, might be more readily purloined, and that much of it was wasted in so many fires, introduced blast furnaces, the fires in which were urged "by large bellows," but these not succeeding, (the blast being too strong,) they had recourse to rotary bellows, (" engines with wheels, carried about with sails like a windmill which fanned and blowed the fire,") but these also failed to accomplish the purpose," so that the Spaniards despairing of the success of their inventions, made use of those which the Indians had framed and contrived." No stronger reason could be adduced why the bellows was not previously used in the reduction of ores.

At a subsequent fusion of the metal in their dwellings, the workmen (says Garcilasso) instead of bellows, continued to use blowing tubes, "though our [Spanish] invention of bellows is much more easie and forcible to raise the fire." Supposing they were ignorant of bellows before the arrival of the Spaniards, here is a proof that after they became acquainted with these instruments, they still preferred their tubes, as the gold and silver smiths of Asia generally do at this day; and hence the use of such tubes does not show, as has been stated, "that they were unacquainted with the use of bellows."

If there was nothing else to adduce in favor of the old Peruvians being acquainted with bellows, or with the principle of their construction and application, than the balsas or blown floats which their fishermen and those of Chili used instead of boats, we should deem them sufficient. These were large bags made of skins of the sea wolf and filled with air. They

a Wilkinson's Manners and Customs of the Ancient Egyptians, iii. 339. b Purchas' Pilgrimage, 223.

were "so well sewed, that a considerable weight could not force any of it out." They carried from twelve to fourteen hundred pounds, and if any air escaped, there were two leathern pipes through which the fishermen "blow into the bags when there is occasion." Frezier's Voyage to the South Seas, page 121. These were real bellows, only applied to another purpose. Had they not been found less efficient or less economical than blowing tubes, they would doubtless have been used as substitutes for the latter in the fusion and reduction of ores. It may here be noticed as a singular fact, and one which may possibly have reference to bellows, that Quetzalcoatl, the Mexican God of the air or wind, was also the Vulcan of all the nations of Anahuac.

Both Mexicans and Peruvians were accustomed from their youth to use blowing tubes, for the primitive air gun, through which to shoot arrows and other missiles by the breath, was universally used, and the practice is still kept up by their descendants. Motezuma, in his first interview with Cortez, shrewdly compared the Spanish guns, as tubes of unknown metal, to the sarbacans of his countrymen. From the expertness acquired by the constant employment of these instruments in killing game, it was natural enough to use them instead of bellows to increase the heat of their furnaces, and custom rendered them very efficient.

We have prolonged our remarks on this subject because it has been concluded that remains of furnaces, found far below the surface in various parts of this continent and in regions abounding with iron, could never have been employed in reducing that metal; for in those remote ages in which such furnaces were in action, the bellows, it is said, was unknown; a position that we think untenable, and quite irreconcilable with the advanced state of metallurgy in those times.

Before leaving the subject of bellows and bellows pumps, we may remark that numerous illustrations of the latter may be found in the natural world. To an industrious investigator, the animal kingdom would furnish an endless variety, for every organized being is composed of tubes and of liquids urged through them. The contrivances by which the latter is accomplished may be considered among the prominent features in the mechanism of animals; and although modified to infinitude, one general principle pervades the whole; this is the distension and contraction of flexible vessels or reservoirs in which fluids are accumulated and driven through the system. On the regular function of these organs the necessary motions of life chiefly depend; by them urine is expelled from the bladder, blood from the heart, breath from the lungs, &c.; they are natural bellows pumps, while other devices of the Divine Mechanician resemble syringes or piston pumps.

The whale spouts water with a bellows pump, and in streams compared with which the jet from one of our fire-engines is child's play. His blowing apparatus consists of two large membranous sacs; elastic and capable of being collapsed with great force. They are connected with two bony canals or tubes whose orifices are closed by a valve in the form of two semicircles, similar to those known to pump makers as butterfly valves. When the animal spouts, he forcibly compresses the bags, already filled with water, and sends forth volumes of it to the height of 40 or 50 feet. The roaring noise that accompanies this ejection of the liquid is heard at a considerable distance, and is one of the means by which whalers, in foggy weather, are directed to their prey. The proboscis of the elephant is sometimes used as a hose pipe, through which he plays a stream in every direction by the pump in his chest. Numerous insects that live in water move their bodies by the reaction of that liquid on streams they eject from

Chap. 2.]

Natural Pumps.

257

their bodies: oysters and some other shell fish move in this manner, Myriads of marine animals also ascend and descend in their native element by means of forcing pumps: when about to dive, they admit water into certain receptacles, and in such quantities as to render their bodies specifically heavier than the fluid they float in; and when they wish to ascend, they pump out the water which carried them down.

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That expert gunner, the jaculator fish, shoots his prey with pellets or globules of water as from a piston pump. When an insect hovers near or rests on some aquatic plant within five or six feet of him, he shoots from his tubular snout a drop of water, and with so sure an aim as generally to lay it dead." The habit of ejecting saliva, which some persons acquire, is by making a pump of the mouth and a piston of the tongue. Other animals practice the same; thus the llama of Chili and Peru, when irritated, "ejects its saliva to a considerable distance"-Frezier says ten paces, or thirty feet. The spurting snake of Southern Africa, it is said, ejects its poison into the eyes of those who attack it with unerring aim. The tongue of the lamprey moves backwards and forwards like a piston, and produces that suction which distinguishes this animal and others of the same family. The sting of some insects, that of the bee, for example, is a very complex apparatus, consisting of a lancet with its sheath, to penetrate the bodies of their enemies; first acting as a trocar and canular, and then as a pump to force poison into the wound-" an awl to bore a hole, [says Paley,] and a syringe to inject the fluid."

It perhaps may be supposed from the form of common pumps, that there is little resemblance between them and these natural machines, but it should be remembered that this form is purely arbitrary, (they are, as we have already seen, sometimes made of flexible materials, and alternately dilated and collapsed like the chests of animals.) The general custom of making them of hollow cylinders and of inflexible materials, arose from experience having proved that when thus made, they are more durable and less liable to derangement than any others that have yet been devised.

The circulation of the blood in man and other animals is effected by apparatus strikingly analogous to sucking and forcing bellows pumps. The heart is one of these-the arteries are its forcing, the veins its suction pipes, and both pump and pipes are furnished with the most perfect valves. By contraction, this wonderful machine forces the blood through the former to the uttermost parts of the system; and by distension, draws it back through the latter. They vary in dimensions as in construction. Some are adapted to the bodies of animals so minute as to be imperceptible to unaided vision, and from these to others of every size up to the huge leviathan of the deep. The aorta of the whale, says Paley, "is larger in the bore than the main pipe of the water-works at London bridge; and the water roaring in its passage through that pipe, is inferior in impetus and velocity to the blood rushing from the whale's heart." Every human being may be considered as, nay is, a living pump. body is wholly made up of it, of the tubes belonging to it, and the liquid moved by it-with such additions as are required to communicate the necessary motion and protect it from injury. Health, life itself, every thing, depends upon keeping it in order. If one of its forcing pipes, (an artery,) be severed, we bleed to death; are any of its sucking tubes (the veins)

His

In the 6th vol. of Machines approved by the French Academy, is the description of a bellows pump, made in imitation of the heart, by M. Bedaut, who named the working part of it "La Cœur," the heart-of which it was a rude resemblance.

www

choked, the parts around them become diseased, like sterile land for want of nourishment; does the pump itself stop working, we instantly die. The regularity and irregularity of its motions are indicated by the pulse, which has always been adopted as the unerring criterion of health and disease, or as an engineer would say, the number of its strokes per minute, is the proof of its state whether in good or bad working order. The pulse not only indicates incidental disorders in this hydraulic machine, but is a crite rion of its age, as well as of its constant condition: the movements are strong and uniform in youth, feeble and uncertain in sickness and age, and as the machine wears out and the period of its labor approaches, its strokes at last cease and its vibrations are then silent for ever.

What mechanic can contemplate this surprising machine without being electrified with astonishment that it should last so long as it does in some people! Formed of materials so easily injured, and connected with tubes of the most delicate texture, whose ramifications are too complex to be traced, their numbers too great to be counted, and many of them too minute to be perceived, and the orifices of all furnished with elaborate valves; that such complicated machinery should continue incessantly in motion, sixty, eighty, and a hundred years, not only without our aid, but in spite of obstructions that are daily thrown in its way, is as inexplicable and mysterious as the power that impels it.

Few classes of men are more interested in studying natural history, and particularly the structure, habits, and movements of animals, than mechanics; and none can reap a richer reward for the time and labor expended upon it. It presents to the studious inquirer sources of mechanical combinations and movements so varied, so perfect, so novel, and such as are adapted to every possible contingency, as to excite emotions of surprise that they should have been so long neglected. There is no doubt that several modern discoveries in pneumatics, hydraulics, hydrostatics, optics, mechanics, and even of chemistry, might have been anticipated by the study of this department of science. Of this truth examples might be adduced from every art, and from every branch of engineering: the flexible water-mains (composed of iron tubes united by a species of ball and socket joint) by which Watt conveyed fresh water under the river Clyde were suggested by the mechanism of a lobster's tail-the process of tunneling by which Brunel has formed a passage under the Thames occurred to him by witnessing the operations of the Teredo, a testaceous worm covered with a cylindrical shell, which eats its way through the hardest woodand Smeaton, in seeking the form best adapted to impart stability to the light-house on the Eddystone rocks, imitated the contour of the bole of a tree. The fishermen's boats of Europe, adapted to endure the roughest weather, are the very model of those formed for her progeny by the female gnat; "elevated and narrow at each end, and broad and depressed at the middle"-the beaver when building a dam-but it is vain to quote examples with which volumes might be filled.

Chap. 3.]

Forcing Pumps with solid Pistons.

259

CHAPTER III.

Forcing Pumps with solid pistons: The Syringe: Its ases, materials and antiquity-Employed by the Hindoos in religious festivals—Figured on an old coat of arms-Simple Garden Pump-Single valve Forcing-pump-Common Forcing-pump-Stomach pump-Forcing-pump with air-vessel-Machine of Ctesibius: Its description by Vitruvius-Remarks on its origin-Errors of the ancients respecting the authors of several inventions-Claims of Ctesibius to the pump limited-Air vessel probably invented by him--Compressed air a prominent feature in all his inventions-Air vessels-In Heron's fountain-Apparently referred to by Pliny-Air gun of Ctesibius-The Hookah.

THE earliest machine consisting of a cylinder and piston that was expressly designed to force liquids was probably the syringe, an instrument of very high antiquity: see its figure in the foreground of the next illustration. To the closed end a short conical pipe is attached whose dimensions are adapted to the particular purpose for which the instrument is to be used. The piston is solid and covered with a piece of soft leather, hemp, woollen listing, or any similar substance that readily imbibes moisture, in order to prevent air or water from passing between it and the sides of the cylinder. When the end of the pipe is placed in a liquid and the piston drawn back, the atmosphere drives the liquid into the cylinder; whence it is expelled through the same orifice by pushing the piston down in the former case the syringe acts as a sucking pump; in the latter as a forcing one. They are chiefly employed in surgical operations, for which they are made of various dimensions-from the size of a quart bottle to that of a quill. They are formed of silver, brass, pewter, glass, and sometimes of wood. For some purposes the small pipe is dispensed with, the end of the cylinder being closed by a perforated plate, as in those instruments with which gardeners syringe their plants.

:

It has been said that the syringe was invented by Ctesibius, being the result of his first essays in devising or improving the pump; but such could not have been its origin, since it is mentioned by philosophers who flourished centuries before him. It was known to Theophrastus, Anaxagoras, Democritus, Leucippus, Aristotle, and their pupils: to the rushing of water into it when the piston was drawn up, these philosophers appealed to illustrate their opposite views respecting the cause of the liquid's ascent, some contending that it proved the existence of a vacuum, others that it did not. To this ancient application of the syringe, most of the early writers on atmospheric pressure allude. "It is pretty strange [observes Desaguliers] that the ancients, who were no strangers to the nature of winds, and knew a great deal of their force, were yet entirely ignorant of the weight and perpendicular pressure of the air. This is evident, because they attribute the cause of water rising up in pumps, or any liquors being drawn up into syringes (commonly called syphons on that account, while pumps were call'd sucking-pumps) to nature's abhorrence of a vacuum; saying, that it fill'd up with water the pipes of pumps under the moving bucket or piston, rather than suffer any empty space. The syringe was in use, and this notion concerning its suction obtain'd long before Ctesibius, the son of a barber at Alexandria, invented the pump." "b

* See Rohault's Philosophy with Clarke's Notes. Lon. 1723; vol. i. 172. Switzer's Hydrostatics, Preface and 172. Chambers' Dict. Articles Syringe, Embolus, Vacuum. Ex. Philos. vol. ii, 249.