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they contrive to take by exertion or by ftratagem. In their choice of animal food they are not remarkably nice. They will. eat the wolf, the hyana, and the myrmecophaga or ant-eater; the leopard, the tyger-cat, and the camelopardalis; and the countryabounds with oftriches, buftards, grous, Guinea-fowls, and partridges. But all thefe, plentiful as they are, would furnish but a precarious fupply for fo confiderable a population; and neceffity has therefore, in all probability, compelled them to call in aid the never-failing fource of plenty and provifion which agriculture affords. The grain chiefly cultivated, as appeared by the famples brought back by the commiffioners, confifted of the holcus Jarghum, a fmaller fpecies of the fame genus which from the reddifh coloured feed appeared to be the Saccharatus, a Dolichos not unlike the cadjan, and a fmall fpatted Phafeolas or kidney bean. Thefe different kinds of grain and pulfe appear to be fown proinifcuously, and, when reaped, to be thrown indifcriminately into their earthen granaries; from whence they are taken and used without felection, fometimes by broiling, but more generally. boiling in milk. It will readily be fuppofed that the art of agriculture among this people is yet in its loweft ftage. In fact, the only labour beftowed on the ground is performed by the women, and with a rude inftrument fomething like the hoe. It is a flat piece of iron fixed into the knob of the Kaffer keerie. When its horizontal edge is fo fitted that it stands at right angles with 'the handle, it ferves as a hoe; when turned round fo as to be parallel with the handle, it is then a hatchet. One of thefe inftru ments appears lying on the gronnd, in the print of the two annexed figures.

"But the Boofbuanas are arrived at that ftage of civilization which is not fatisfied with the mere neceffaries of life supplied to them abundantly from the three fources of agriculture, grazing, and hunting; they are by no means infenfible of its conveniences and its luxuries. Their skin cloaks for the winter are pliant, foft and warm, being frequently lined with the fur-fkins. of tyger-cats, viverras and other fmall animals; and when in fummer they go without clothing, they rarely expofe their bodies to the rays of the fun, but carry umbrellas made of the broad feathers of the oftrich fixed to the end of a stick. They vary their mode of dreffing both animal food and grain, occafionally boiling, broiling, or roafting the former, and fimply broiling the latter, or bruifing it into flour and boiling it up with milk. Among the luxuries of the appetite tobacco feems to hold the higheft eftimation. Both men and women are paffionately fond of drawing the fioke of this narcotic herb through water, poured ufually into the horn of the cow or the eland, through the fide of which the tube of the tobacco-pipe is inferted. Of fnuff they are equally fond. This article is compofed of a variety of ti mulant plants dried and rubbed into duft, which is ufually mixed with wood-afhes; of this mixture they take a quantity in the

palm

palm of the hand, and draw it into the noftrils through a quill or reed till the tears trickle down their cheeks. Children even of four or five years of age may be obferved taking fnuff in this manner. Their bodies they carefully ornament with devices painted with white pipe-clay and red ochre; their hair they fometimes cut in a peculiar manner, leaving a high taft on the crown of the head, not unlike the fafhionable crops of the prefent day, to which is frequently appended the tail of a hare, or a diftended bladder of this or fome other fmall animal; or the wings of the Numidian crane are fixed erect on each fide of the head. A triangular plate of copper is almoft invariably fuf pended from one ear, and the teeth and the claws of lions and leopards are worn as necklaces. To thefe fpoils of the chafe the men add rings of ivory, cut from the elephant's tufk, round the upper part of the arm; and the women ufe thongs of leather,fometimes plain and fometimes decorated with beans and bits of copper, round the legs and arms. Every man had a knife flung about the neck by a leather thong, and fitted into a scabbard..a The blade is generally about fix inches long, an inch broad, rounded at the end, and brought to an edge on each fide; the handle fometimes of wood, and fometimes of ivory; in the lata ter cafe, it is ufually carved into the fhape of the elephant's pro.. bofcis. The party had with them a quantity of common knives intended for barter, but the Boshuanas held them very cheap, obferving that their own were at leaft twice as good, because they were made to cut with two edges, whereas those of the white people only cut with one. The knife, in fact, is so useful?! an inftrument to fuch as live by the chafe and on roots, that it may almost be confidered as an article of the firft neceffity, and is valued accordingly. A Boofbuana is accounted wealthy according to the number of cattle, knives and beads he may poffefs; thefe are the money and the currency of Lectakoo.

"The Boofbuana women not only performed the task of hoe. ing the ground, reaping the grain, clearing it from the hufk, and bearing it into the granaries, which with all the other inferior earthen veffels were the work of their own hands, but they col lected most of the materials, and in a great measure prepared them for the construction of the dwelling-houses. The men employ a confiderable portion of their time in hunting, in preparing kins and hides for cloaks and fhoes; and they have the fole care of the cattle and of the dairy." P. 393.

We fhall be truly rejoiced to hear that Mr. Barrow's materials are not yet exhaufted. His narration is always fo agreeable, his obfervations fo judicious, his geographical knowledge fo extenfive, that every fubject he undertakes to difcufs comes from his hands replete with important infor mation. His different volumes claim a refpectable fituation:

in the clafs to which they belong, and will have a place in every well chofen library

The prefent publication is adorned with twenty-one plates on different fubjects, of which the chart, illuflrative of the expedition into the interior of Africa, is the most interefting and the most valuable.

ART. VII. Philofophical Tranfactions of the Royal Society of London, for the Year 1806.

G. and W. Nicol. 1806.

Part I. 410. 237 PP

THIS part of the Philofophical Tranfa&tions contains nine papers, befides the meteorological journal, which forms an appendix of 26 pages. The contents of those papers are as follows.

1. The Croonian Lecture on the Arrangement and Mechanical Action of the Mufcles of Fishes. By Anthony Carlisle, Efq..

F.R.S.

The conftruction of the muscles of fishes, this author ob ferves, is very different from that of the muscles of other animals. They have no tendinous chords; their infertions being always fleshy.

"There are, however, femi-tranfparent pearly tendons placed between the plates of mufcles, which give origin to a series of fhort mufcular fibres paffing nearly at right angles between the furfaces of the adjoining plates. Lewenhoeck appears to have overlooked thefe tendons, and the numerous veffels which he defcribes in the interftices of the mufcular flakes, I have not been able to difcern." P. z.

Another peculiarity of this clafs of animals is, that their mufcular flesh is remarkably large; yet its power is almoft entirely intended for the lateral flexure of the fpine and tail, which is not very great; whilft the fins are moved by small muscles of comparatively small power.

In order to determine the real action of the fins in the mo tion, and the equipoife of fifhes, this author made feveral experiments on a number of living dace, on the roach, the gudgeon, and the minnow. From which it appears, upon the whole, that each of those fins is capable of four motions: viz. of flexion and extenfion, and of expanding and closing the rays. Their action ferves for the purpofes of turning,

ftopping,

ftopping, altering the pofition of the fith towards the horizon, and for keeping the back upwards: while the action of the tail is the principal organ of the animal's progreffive motion, and this is put in action by the great mafs of lateral mufcles. A defcription of the mechanical arrangement and phyfiology of the lateral mufcles of the bodies of fifhes, forms the prin cipal part of the prefent paper; and for this purpose the cod fish was felected, as a ftandard of comparifon for the mufcles of other fishes; there being a confpicuous resemblance among them all. A plate, with the delineation of a cod partly diffected, is annexed to this paper.

The particulars, which are principally defcribed by this author, are the fhapes, directions, and infertions of the mufcles; together with the difpofition of the principal nerves and blood veffels, which give them nourishment and action.

II. The Bakerian Lecture on the Force of Percuffion. By William Hyde Wollafton, M.D. Sec. R.Š.

This lecture contains fome general remarks on a branch of mechanics, which has always been, and fill continues to be, much controverted among philofophers. The question is, whether the forces of bodies in motion are as the quantities of matter multiplied by the velocities, or as the quantities of matter multiplied by the fquares of the velocities. For inftance, if two equal bodies move with velocities that are as one to two; are their forces to be reckoned as one and two, or as one and four? Leibnitz and his followers are of the fatter opinion; whilft thofe who efteem themfelves Newtonians, entertain the former; yet Dr. W. obferves, that Newton's explanation of his third law of motion is by no means favourable to the defenders of that opinion.

Unluckily, the experiments which have hitherto been de vifed for the decifion of this controverfy admit different interpretations; hence, if poffible, a new experimental inveftigation ought to be inftituted; but previous to this, a clear and definite ftatement of the various meanings of words and ideas must be agreed upon, in order to prevent ambiguity and perplexity. This author's remarks in the prefentpaper are almoft entirely confined to thofe meanings, and for this purpofe he briefly mentions certain explanations and definitions of Newton, Bernouilli, and Smeaton.

III. Memoire fur les Quantités imaginaires. Par M. Buće. This extensive paper is printed in the French language. Its objca is to fhow the meaning and the application of

imaginary

imaginary quantities. This author commences by difcrimi nating, with great perfpicuity, the various fenfes in which the algebraical figns of plus and minus may be used; not only in an algebraical fenfe, confidering algebra as an univerfal arithmetic, but likewife in a geometrical fense and he particularly points out thofe cafes, and thofe limitations, within which a negative quantity may be understood to stand by itfelf. He then gradually proceeds to confider the generation of thofe quantities which mathematicians call imagin ary; viz. those negative quantities to which a radical index of an even denomination is annexed; fuch as ; or 8,

&c. which neceffarily refult from certain algebraical operations; it being acknowledged by mathematicians, that the roots of fuch quantities cannot be extracted; or, rather, that they have no affignable root, from which circumftance they have been denominated imaginary quantities.

The object of this author's views, is to contrive and examine physical and geometrical cafes, into which the abovementioned imaginary quantities do enter, and to afcertain how far a certain meaning may be annexed to them. This fubject is undoubtedly abftrufe; yet the ingenuity with which it is handled in the prefent paper, tends coniderably to fettle the meanings or the ideas which ought -to be annexed to thofe expreflions. In the course of this elucidation Mr. B. adopts Mr. Carnot's notation, as well as feveral ftatements of that diftinguifhed algebraift. He alfo examines fome of Carnot's problems, and pro-pofes others, which he likewife analyzes under all the forins of folution they are capable of; and for this illustration a plate of diagrams accompanies the paper.

Towards the latter part Mr. B. fhows the ufes that may be made of the imaginary quantities.

As it would be impracticable to give our readers a better idea of the fubject of this paper, without a long train of reafoning and illuftration, we fhall only tranfcribe the ftatement of one of this author's problems, merely as a fpeci men of his ftyle.

"Probleme V. Un marbrier a deux cubes de marbre. Le coté d'un de ces cubes excède le coté de l'autre, de deux piés, et le nombre des piés cubes contenus dans les deux eft 28. Quelles font les dimenfions de ces deux cubes?

**Avant de donner la folution de cette queftion, j'ai une remarque à faire.

"Cette question conduit à une équation du ze dégré. Toute quation du ge dégré a au moins une racine réelle. Par confé

quent

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