Page images
PDF
EPUB

but who is to execute his plan? We have no hopes from the yearly emigration of British travellers; their pursuits are of a different kind; and were they willing to undertake, we are afraid that very few of them indeed would be found able to perform the talk. Could the different governments in Europe be induced to fend out travellers capable of realifing the ideas of the author, and were their reports from time to time made the bafis of laws and regulations for the improvement of the national system, the confequences would be highly falutary to fociety. But nations, like individuals, are too often careless of their best concerns. For reasons of this kind we are afraid that the work before us will not be productive of all those advantages which it is certainly calculated to promote.

The fecond volume contains a catalogue of travels, and of books relative to that fubject, arranged in such a manner that the reader may at once find the town or country concerning which he wishes for information.

Would the fenfible and laborious author of this publication condense his work, we mean, would he give the effentials of it in a smaller form, we doubt not of its being more univerfally ufeful, because it would then have a better chance of being used as a travelling vade mecum.

ART. XI. Philofophical Tranfactions of the Royal Society of London, Vol. LXXVII. For the Year 1787. Part II. 4to. 8s. 6d. fewed. Davis. London, 1787.

OF

F the First Part of this volume we gave an account in our laft Review; we now proceed to the Second Part, which

begins with

Article XXI. An Experiment to determine the Effect of extirpating one Ovarium upon the Number of young produced. By John Hunter, Efq. F. R. S. In this experiment the spayed fow neither bred fo long, nor brought fo many pigs, in an equa number of farrows, as the perfect one. In the first eight litters the number produced by the former was seventy-fix, and that by the latter eighty-feven. The fpayed animal farrowed no more; but the perfect one, in eight additional farrows, brought feventy-fix pigs. Mr. Hunter thence thinks it probable that the ovaria are from the beginning deftined to produce a fixed number, beyond which they cannot go, though circumstances may tend to diminish that number; and that the conftitution has no power of giving to one ovarium' the capacity of propagating equal to two. A fingle experiment may indeed not be decifive of these facts; but the great expence with which every repetition

of

of it must be attended, is fufficient to discourage the most zealous inquirer from profecuting the subject any farther.

1

Art. XXII. Experiments made to determine the pofitive and relative Quantities of Moisture absorbed from the Atmofphere by various Subftances, under fimilar Circumftances. By Sir Benjamin Thompson, Knt. F. R. S. The fubftances used in these experiments were sheep's wool, beaver's fur, the fur of a Ruffian hare, eider down, filk, linen, and cotton wool. It was found that the firft of thefe abforbed the greateft quantity of moisture, and that the abforbing power of the others diminished progreffively in the order in which we have ftated them. Sir Benjamin Thompson very juftly afcribes to a difference in the absorbing power of thefe feveral fubftances the different effects which they produce when worn next the skin. One of them feels warm because the moifture is immediately abforbed; and another cold and moift, from its greater refiftance to the admiffion of the perspirable fluid. On the fame principle, rather than its warmth, depends the power of woollen in promoting perfpiration.

[ocr errors]

Art. XXIII. The Principles and Illustration of an advantageous Method of arranging the Differences of Logarithms on Lines graduated for the Purpose of Computation. By Mr. William Nicholson. This paper contains a series of computation, and of defcriptions illuftrated by diagrams. The scale is a circular one, compounded of Gunter's scale of a sector; an improvement equally fuited to utility and convenience.

Art. XXIV. Observations tending to fhew that the Wolf, Jackal, and Dog, are all of the fame Species. By John Hunter, Efq. F. R. S. Mr. Hunter has collected several inftances to prove that the wolf and the dog breed together, and that their progeny is prolific; but the inferences that they are really of the fame species, feem not to be quite fatisfactory. The probability only is that they are of a fimilar kind. The inftances are taken from confined animals; and with the final caufe affigned, it can be of no weight in the argument, as the copulation of those animals is not likely ever to take place in a state of nature.

Art. XXV. Experiments on the Congelation of the Vitriolic Acid. By James Keir, Efq. F. R. S. It appears from thefe experiments, that the medium denfity of the acids which did freeze with the cold of melting fnow was 1780; and that, at the denfities of 1790 and 1770, the acid had been incapable of freezing with that degree of cold. It farther appears, that by applying a more intense cold, namely, that produced by a mixture of fnow, falt, and water, the limits of the denfity of the acids. capable of congelation were extended to about above or below the point of eafieft freezing. There feems little reafon to

N 3

doubt

doubt that, by greater augmentations of cold, thefe limits may be farther extended; but in what ratio these augmentations and extensions proceed, cannot be determined without many obfervations made in different temperatures.

Art. XXVI. An Account of fome Experiments on the Production of artificial Cold. By Thomas Beddoes, M. D. The experiments which are the subject of this paper had been made by Mr. Walker, apothecary to the Radcliffe Infirmary. He found that by adding fucceffively fal ammoniac, nitre, and Glauber's falts, while they held the water of cryftallifation to water, the thermometer funk to forty-fix degrees. When materials, previously cooled, were employed, the diminution of heat was more confiderable; and by adding fuch materials to cooled diluted fpirit of wine, the thermometer funk to four. Experiments were likewife made with fome other fubftances for the fame purpose, and the results of them are mentioned.

Art. XXVII. An Account of a Doubler of Electricity; or a Machine by which the least conceiveable Quantity of positive or negative Electricity may be continually doubled, till it becomés perceptible by common Electrometers, or visible in Sparks. By the Rev. Abraham Bennet, A. M. The author of this article fuggefts an ingenious method of rendering fmall quantities of electrical fluid, in the air, perceptible to the fenses; and he has added to the method a journal of the electrical state of the air from the 23d of January 1787 to the 2d of March. In general the electricity was pofitive, except in rain; it was then univerfally negative, unless the rain had owed its origin to the accumulation of water in mifts; a cause very different from that which produces rain in the ufual form. The negative electricity feems to be connected with foutherly winds, because these are connected with rain; for it was found that when rain occurred, with the wind even from the north-west and the weft, the electricity was ftill negative. We wish to see these observations attentively profecuted.

Art. XXVIII. Some Particulars relative to the Production of Borax. By William Blane, Efq. This faline fubftance is brought from Jumlate, a kingdom in the mountains of Thibet. The place where it is produced is defcribed to be in a fmall valley, furrounded with fnowy mountains, in which is a lake, about fix miles in circumference, the water of which, from hot fprings by which it is fupplied, is constantly hot, fo much fo that the hand cannot be held in it for any time. The earth round the lake is full of a faline matter, in fuch plenty that, after falls of rain or fnow, it concretes in white flakes upon the furface, like the natron in Hindoftan. Upon the banks of this lake, in the winter, when the falls of fnow begin, the earth is formed into small refervoirs,

by

by raifing it into ridges about fix inches high. When these are filled with fnow, the hot water from the lake is thrown upon it, which, with the water from the melted fnow, remains in the refervoir, to be partly absorbed by the earth, and partly evaporated by the fun. After this, there is found at the bottom a cake of crude borax, which is taken up and afterwards refined by boiling and cryftallisation.

Art. XXIX. A Letter from the Father Prefect of the Miffion in Thibet, F. Jofeph da Rovato, containing fome Obfervations relative to Borax. The account in this article agrees with that in the preceding, in defcribing borax as a natural, not an artificial production; but the Father Prefect tells us that the subftance is procured from rain. It is probable that the hot springs mentioned in the former narrative, diffolve the borax in large quantities; and the fnow may be neceffary to cool the water, in order that the falt may cryftallife; while, in the fecond account, if by rain-water is understood the rain collected in falling from the neighbouring hills, the evaporation by the fun is fufficient to exhale the fuperfluous fluid.

Art. XXX. Sur les Gas Hepatiques. Par Monf. Haffenfratz. On Hepatic Air. By M. Haffenfratz. Mr. Kirwan had before given it as his opinion that hepatic air was only fulphur in an aerial state; but M. Haffenfratz has been able to hepatife many different kinds of air, and maintains that hepatic gas is only fulphurated air of different kinds. He fulphurated nitrous air, atmospherical mephitis, vital, and atmospherical air.

Art. XXXI. Botanical Defcription of the Benjamin Tree of Sumatra. By Jonas Dryander, M. A. This tree has been often mistaken by botanifts. By Ray it was supposed to be a Virginian plant; while others confounded it with the croton, the mantiffa, the terminalia, the laurus, &c. It is now afcertained, however, from a dried fpecimen, to be a fpecies of ftyrax.

Art. XXXII. An Account of an Experiment on Heat. By George Fordyce, M. D. F. R. S. This experiment relates to the communication of heat, but leads to nothing new on the fubject.

Art. XXXIII. An Account of an Observation of the Right Afcenfion and Declination of Mercury out of the Meridian, near his greatest Elongation, September 1786. By Mr. John Smeaton, F. R. S.

Art. XXXIV. A remarkable Cafe of numerous Births, with Obfervations. By Maxwell Garthfhore, M.D. F.R.S. and A.S. This cafe is well authenticated, beyond the evidence ufually accompanying fimilar narratives. The birth confifted of five infants, all females. Two of them were born alive, and the whole number within fifty minutes. The mother had before been delivered

N 4

delivered of a fingle child; and the husband, who had been in an infirm ftate for fome years, was, at the time of this incident, dying in a confirmed confumption. Dr. Garthshore gives a fhort account of other numerous births in Great Britain; and fpecifies the proportion in which they are observed to happen in different countries,

Art. XXXV. Chloranthus, a new Genus of Plants, described by Olof Swartz, M.D. This new genus is a Chinese plant, neither beautiful nor ufeful, and may be arranged in the fortyeighth natural order, next to the vifcum. The name given it is inconfpicuus,' from the fmallnefs of the flower.

Art. XXXVI. On the Preceffion of the Equinoxes. By the Rev. Samuel Vince, M. A. F. R. S. The preceffion is calculated to be 21" 6" in a year; but as in the inquiry the earth is supposed to be of an uniform denfity, and the proportion of the equatorial and polar diameters to be fixed, the calculation muft probably deviate a little from the truth.

Art. XXXVII. Abftract of a Regifter, of the Barometer, Thermometer, and Rain, at Lynden, in Rutland, in 1786. By Thomas Barker, Efq. Alfo of the Rain at South Lambeth, in Surrey; and at Selbourn and Fyfield, Hampshire. The variation of the thermometer was from 80 to 11, which is greater than commonly happens. The barometer varied from 30.05 inches to 29.01. The rain at Lynden this year was 27.289 inches; at South Lambeth 22.43; at Selbourn 39.57; and at Fyfield 29.60: 29.72 on an average.

Art. XXXVIII. Obfervations on the Structure and Economy of Whales. By John Hunter, Efq. F. R. S. The fpecies here examined are the delphinus phocoena, or porpoife; the grampus; the delphinus delphis, or bottle-nofed whale; the balæro roftrata; the balalan myfticetus, or the whale-bone whale; the phyfeter macrocephalus, or the fpermaceti whale; and the monodon monoceros, or the nar whale. In general, the tail of thefe animals is flattened horizontally, to enable them to rife, in order to breathe; the flesh is very red, and of greater fpecific gravity than beef, so that the large quantities of fat are a neceffary part of economy in thefe various fpecies. What is called fpermaceti is found every where in the body in fmall quantity, mixed with the common fat of the animal, bearing a very fmall proportion to the other fat. In the head it is the reverse; for there the quantity of fpermaceti is large when compared to that of the oil, though they are mixed together as in other parts of the body. The following remarks are particularly worthy of being extracted:

Although this tribe cannot be faid to ruminate, yet in the number of ftomachs they come nearest to that order; but here I fufpect

that

« PreviousContinue »