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is no eafy task to difengage thefe principles from the obfcurity
thrown on them by the ruft of antiquity; as appears, fufficient-
ly, from the imperfect accounts that have been given, by learn-
ed men, of the manner of placing the rowers in the ancient Tri-
remes, or Galleys, fuppofed to have had three rows or benches
of oars.
Our Author, to render his researches on this intricate
fubject more fuccefsful than thofe of the Scaligers and other
mere philologifts, made feveral voyages in the feas of the Levant,
in rowing vellels of various kinds. The refult of his inquiries
and labours we have in the work before us; which is divided into
feven books. In the first and fecond he treats particularly of
thofe veffels, or rather great rafts or floats, with which the Ty-
rians, their inventors, made their firft expeditions along the coafts,
and which received from time to time, new degrees of improve-
ment, until the reign of Sefoftris, King of Egypt, when they
gave place to long veffels, which rendered navigation more ex-
peditious. It is remarkable, obferves our Author, that in thefe
two firft periods of the marine of the ancients, the rafts and long
veffels were fo happily conftructed, that the navigators, were
fcarcely ever expofed to the danger of perishing, a point which
has not yet been attained to by the modern marine, however perfect
it may appear, when compared with the rude beginnings of na-
vigation in the early ages.-In the following books M. LE ROY
lays before us an account of the knowledge which, the Greeks
acquired in maritime affairs, from the period, when they began
to diflinguifh themfelves by efforts of genius, to the end of the
Peleponnefian war. After this period, he unfolds the whole
fyftem of their military marine, examines the different hypothe-
fes that have been employed to explain the Triremes, Quinque-
remas, &c. and then confirms his own fyftem by reafon, obfer-
vation and experience. His obfervations on the ufe that might
be made (in conftructing veffels of a lighter kind) of the know-
ledge of the marine of the ancients, are judicious and folid; and
this treatife, on the whole, has very great merit. It will be fol-
lowed by another on the marine of the Romans.


VII. Memoire, qui a ramporté le Prix propofé par l'Academie de Lyon, &c. i. e. A Differtation (which obtained the Prize propofed by the Academy of Lyons) on the following Question: HAS THE ELECTRICITY OF THE ATMOSPHERE ANY INFLUENCE ON THE EFFECTS OF THE HUMAN BODY AND WHAT THAT INFLUENCE? By M. DE THOURRY, of the Oratory. This ingenious Author fuppofes that electricity or the electrical fluid (terms that are often fynonimous) is nothing more than that elementary fire, which pervades the whole univerfe, combined with a phlogifton, more or lefs fubtile according to the fubftances, from whence it proceeds. The atmosphere is electric, as it is always impregnated with a phlogifton, formed by the oily


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and fulphureous vapours, exhaled from the earth, and the bodies which cover its furface; and it has been often demonftrated, by feveral writers, that the electricity of the atmosphere has an influence upon the animal ceconomy. Among the various effects of this influence, our Author reckons two, that have more particularly employed his refearches, and these are firft, the colour and perfection of blood, and fecondly animal motion.

As to the firft, our Author's reafoning amounts to what follows: From experiments well known and easy to be repeated it appears evident, that milk affumes a red colour by the addition of acid or nitrous particles: And as the electrical fluid contains fuch partia cles in its phlogifton, it may, by its mixture with the blood, produce the red colour of that fluid. Sir Ifaac Newton proved that no fluid changed its colour, but by fome new modification in the fize of its molecules, or in its fpecific gravity: and hence it may be concluded, that the electrical fluid, entering into the blood, muft change the fize and fpecific gravity of its molecules, and thus change the reddifh hue, which the blood has, when it enters the lungs, into the deep red, or vermilion, which it has contracted, when it iffues from them. It happens in fact, that when blood, drawn from the vein, becomes difcoloured, and lofes its clear and vivid hue, this hue is immediately restored by beating it brifkly with a little rod; now the only addition that is made to it by this method of proceeding, is air (impregnated with the electrical fluid) and motion. Several experiments, made by Dr. Priestley, tend to confirm this theory, by fhewing that electricity joined with air gives a red tincture to blue liquors.Our Author proceeds thus:

The electrical fluid is active and volatile, like fire, eafily fixed, like earth, and is, by its nature, fufceptible of being compounded and decompounded, like liquids. On its approach to the bloodveffels, it expels from thence fuperfluous humours; if, in the molecules of the blood, it meets with heterogeneous principles, it decompounds them, unites itfelf to thofe, which are analogous to its nature, and by its action, facilitates the junction of the other molecules to the particles that are fimilar to them.

As to the fecond effect of the influence of electricity, our Author obferves, that it is afcertained to be the principle of motion in plants, and known to contribute to their growth, by repeated experiments: Now as all organized bodies, whether animated or inanimate, vegetate and grow pretty much in the fame manner, Mr. THOURRY thinks himself authorised, by this confideration, to attribute animal motion or (as he calls it) the motion of the animal machine to the electrical fluid, as its principle and caule. According to trials made on various occafions, it appears that this fluid augments, alfo, animal motion, and never fails to renew it, when it is fufpended or deftroyed; it accelerates the cir


culation of the fluids in the human body, procures often hæmorrhages, and cures feveral of thofe nervous complaints that pass under the name of vapours *.

After having mentioned the effects of electricity on fingers, that had been motionlefs for the space of feveral years, and alfo the cafe of a perfon who had loft the ufe of both his arms, and was cured by natural electricity, (i. e. by being ftruck with thunder) our Author propofes his conjectures concerning the manner in which these electrical phenomena, or effects of electricity are produced. He fuppofes that there are in Nature, three principal fprings of action, three fuperior univerfal agents, the etherial matter or primitive fire,-electrical matter-and air, which are mutually fubject to each other. In the human body, he obferves, in the first place, three other SUBORDINATE agents, the nervous fluid, the blood, and the lymph, with their ducts, and in the second place, three folids that are to be moved, muscles, cartilages, and bones.

Of the three univerfal agents of the firft clafs that may be called external with refpect to the body, our Author confines his inquiry to the fecond (the electrical fluid) because it is this, which derives its action from the first, (the ether) and communicates action to the third, (the air).-To fet this agent in motion we have as yet, fays our Author, no other means but friction: Nature has, certainly, another method of operation; for we do not fee, what kind of friction could amass together in the clouds the different parts of the electrical fluid, that must be collected in order to produce thunder.

Having thus prepared his agents, our Author proceeds to confider their operations and effects. He fuppofes, in the first place that the cortical fubstance of the brain contains pofitive or plus electricity, and that the medullary fubftance contains negative or minus electricity Secondly that thefe two fubftances have, each, their respective and peculiar conductors, that is, nerves that convey plus electricity and nerves that convey minus electricity: the latter carrying the electrical fluid from the extremities to the brain, and the former tranfmitting it to the muscles and extremities:-Thirdly that thefe fubftances have, in the brain, a repository in common (fuch as the pineal gland, its bafe, &c.)

Our Author does not adopt the opinion of thofe, who maintain that electricity augments equally and in all circumstances the velocity of the pulfe. But his experiments on this part of the animal œconomy and their refult appear, to us, very curious. This refult is, that when the pulfe is too flow electricity accelerates it, when it is too quick, electricity retards it, and leaves it pretty much as it is, when it is in its right ftate. The experiments, that led to this conclufion, were published in a differtation prefented by our Author to the academy of Caen, in 1773.


for the common fenforium: Fourthly that, befides their particular and respective fluids, all the ducts contain as much of the electrical fluid as is neceflary to the circulation and to the functions of thefe fluids in the human body; and finally, that all thefe fluids are in equilibrio, and at reft.

From these hypothefes our Author explains the fenfations in the following manner. From a body, that is touched, electrical molecules proceed, which are pumped by the nerves or minus conductors. As a plenum is fuppofed, a quantity of thefe molecules cannot enter at one extremity without an equal quantity be emitted at another; the equilibrium is thus immediately broken in the medullary fubftance, and the motion is communicated to the fenforium, fo that the foul, in confequence of the laws of its union with the body, receives notice of the actual ftate of the latter, with respect to that fenfation. The cafe is the fame in the fenfations relative to the tafte, as here external bodies affect immediately the organ, as in the fenfe of touching.

The impreffion (continucs our Author) made by the ambient air on the tympanum of the ear produces the phenomena of hearing. The acoustic nerves, the greatest part of which are minus electric, pump the electricity from the tympanum and the air by which it is fet a going, and the motion is communicated to the brain.

The organ of fmelling is affected by the odoriferous particles, which proceed from bodies: Thefe particles are a fubtile phlogifton, which, by its conjunction with the etherial fire, forms electricity. The etherial fire lays hold of it in its paffage to the organ of fmelling: and thus combined into an electrical fluid they are carried by the minus conducting nerves to the fenfo


As to vifion, we know it is performed by rays of light reflected from the feveral points of objects, refracted alfo and collected in their paffage through the coats and humours of the eye to the retina, where they make an impreffion that is conveyed by the optic nerve to the brain. Now this light, according to our Author, is nothing more nor lefs than the etherial fire, which, at its entrance into the eye, finds there molecules of the phlogifton, to which it adheres, or joins itfelf, in its paffage to the optic nerve to render the fenfation more intenfe and lively.

Mr. THOURRY imagines, that the fecretion of the humours from the mafs of the blood in the human body, depends principally upon this circumftance, that the fmall fibres or molecules, which compofe the texture of the fecretory ducts, have fomething in their nature peculiarly analogous to the refpective fluids that pafs through them, by which each fluid is attracted, and goes, by affinity, to its proper pore. But there is nothing new in this conjecture; it comes pretty much to the fame with the opinion of


Winflow, who maintained and proved by various experiments, that in order to fecretion it is not only neceffary that the pores of the ftrainers or fecretory ducts be of different diameters, but also that the parts of thefe pores be already imbued or moistened with a liquor, like that they are to filtrate.

When by a mechanifm of this kind the lymph is difengaged from heterogeneous particles, it circulates in its veins, which are ramefied like thofe of the blood, and which at certain diftances have the glands for their repofitories or refervoirs: There is a multitude of little excretory ducts through which the lymph paffes and lofes itself in the fleshy parts, where it adheres to the molecules of its kind, which it meets with there. But the vifcidity of the lymph is fuch, according to our Author, that it could never arrive there, if it had not fuch an active and powerful vehicle, as electricity, which attenuates it, and alfo carries and pushes it forward to its laft entrenchments, while, by means of perfpiration it exhales the ferous particles, and evaporates with them, and thus nutrition is performed.-The experiments, reafonings, and conjectures, that form the contents of this little work, are proofs of the industry and capacity of the Author. The first are, for the most part, curious, the fecond are frequently folid, and the third are often plaufible, and fometimes ingenious.


For MAR C H, 1778.

Art. 9. A Differtation on Cancerous Difeafes. By Ber. Peyrilhe,
M. D. Regius Profeflor of Surgery, and Member of the Royal
Academy of Surgery at Paris, &c. &c. Tranflated from the La-
tin, with Notes. 8vo. 2 s. 6d. Wilkie. 1777.


N confequence of a prize offered by the academy of fciences at Lyons for the beft differtation on the nature and method of cure of cancerous diseases, feveral treatifes on the fubject were offered, of which that before us obtained the preference. The Author begins with attempting to establish his idea of cancer; which is, that a ftagnation of the lymph firft produces a tumour in a gland, which, by continual acceffions, compreffes the neighbouring parts, and caufes that induration which is termed a Schirrus: that either from fome external cause, or conftitutional difpofition, a kind of fermentative process, of the putrefactive fpecies, begins in the center of this tumour, which diffolving part of the mafs, occafions a fluxion of corrofive fluid towards the furface, and terminates in an open ulcer. He therefore opposes the idea of an innate cancerous virus fui generis, and contends, that the humour to which this name is applied differs in no refpect from the fanies produced by every animal putrefaction. In confequence of this theory, the treatment he propofes is entirely upon the antifeptic plan; and he particularly recommends the external application imephitic vapours, apparently without any previous informa

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