THE MONTHLY REVIEW For NOVEMBER, 1755. ART. XXXIX. Philofophical Transactions, giving some account of the present undertakings, studies, and labours of the ingenious, in many confiderable parts of the world. Vol. XLVIII. Part 2. for the year 1754. 4to. 12s. Davis. I N our Review, vol. XI. we gave an account of the first part of this volume; the second contains fifty articles, viz. from 58, to 107 inclusive. Art. 58. A Treatise on the Precession of the Equinoxes, and in general on the motion of the nodes, and the alteration of the orbit of a planet to the ecliptic. Translated from a French manuscript of St. Jaques Silvabelle, by J. Bevis, M. D. The preceffion of the equinoxes is one of the most curious parts of astronomy; and the lovers of that science are greatly indebted to the ingenious author, for a treatise, not founded on any arbitrary hypothesis, but on the invariable laws of nature. It is divided into four sections; the first treats of the motion of the pole of the terrestrial equator, caused by the sun: the second, of the motion of the pole of the terreftrial equator, caused by the moon: the third, of the motion of the pole of a ring, or of the orbit of the moon, caused by the fun: and the fourth contains the application of the formule, found in the other sections. In this paper the author has shewn, that there are five * distinct motions of the pole of the earth; namely, two of precession, which are parallel to the plane of the ecliptic, ' and three of ofcillation on the plane of the ecliptic. Y That That the two of precession are caused, the one by the sun, • the other by the moon. That which is caused by the fun is • conftantly the fame, at every quarter of the time of the revolution of the fun round the earth, that is, every three • months: that which is caused by the moon is constantly the • same at every quarter of the time of the revolution of the • moon round the earth; that is, about every seven days. That of the three motions of ofcillation, one is caused by the fun, and is compleated in the space of a femi-revolution • of the fun round the earth, taken from one equinox to the • following one, that is, in fix months. That the other is caused by the moon; and that each ofcillation is completed in the space of a semi-revolution of ⚫ the moon round the earth; that is, in about fourteen days. • That the third is caused likewise by the moon, and arises • from the plane of her orbit being different from the plane of ⚫ the ecliptic, and from the pole of the lunar orbit making • its revolution about the pole of the ecliptic, that is, in about eighteen years and two thirds. That there is a relation purely geometrical between the ⚫ quantity of the nutation, during the time of the semi-revo• lution of the pole of the lunar orbit, and the quantity of the • precession, caused likewise by the moon in the same time. And that this relation is quite independent of the force of the moon, of the quantity of the earth's flatness, of the quantity of the terrestrial matter, and, in a word, of every thing ⚫ of a physical nature, that can enter into the problem.' Art. 59. A Letter to the right honourable George earl of Macclesfield, P. R. S. concerning the ages of Homer and Hefiod. By George Coftard, M. A. Sir Ifaac Newton, from calculations made from the achronical rifing of Arcturus, supposes that Hefiod flourished about 879 years before Christ; but Mr. Coftard has shewn, that these computations are uncertain; and that Hefiod might have lived in the 595th year before Chrift, for any thing that can be gathered to the contrary from the achronical rifing of that star. He has also endeavoured to shew, from other astronomical data mentioned by the poets, that Homer and Hefiod, who are generally supposed to be contemporaries, did actually live about that time; which is above 300 years later than Vellius Paterculus placed them, and more than 400 later than Petavius. But what renders this article of real use (the fixing the time in which Homer and Hefiod flourished being of little consequence) is, that Mr. Coftard, by examining what has been faid by the antients relating to this subject, has given us a succinct account of the rife and progress of astronomy among them, by clearing its history from fable and mythology. Art. 60. An additional remark to one of Mr. William Watson, in his account of the Abbé Nollet's letter concerning electricity. By Thomas Birch, D. D. Secr. R. S. The remark to which this is an addition, relates to the antients having observed fome of the phænomena of electricity: Cafar in his history of the African war, exprefly says, that in a violent stormy night, Legionis pilorum cacumina fua sponte arserunt: and Livy mentions two similar facts. To these Dr. Birch adds another from Fynes Morifon, who, in his itinerary, says, that at the siege of Kingfale, by the Lord Deputy Mountjoy, on the 23d of December 1601, there was much lightning, tho' the night was clear. • And I have heard,' adds he, 'by many horsemen of good credit, and, namely, by Captain • Pikeman, a gentleman of good estimation in the army, that ⚫ this night our horfemen, set to watch, to their seeming, did • see lamps burn at the points of their staves, or fpears, in • the midst of these lightning-Aashes.' Art. 61. Extract of a letter of the rev. Mr. Joseph Spence, professor of modern history in the university of Oxford, to Dr. Mead, F. R. S. This is a very short article, and only mentions a statue and two busts found at Herculaneum. Art. 62. A letter to the right hon. George earl of Macclesfield, P. R. S. concerning the value of an annuity for life, and the probability of survivorship. By Mr. James Dodfon. Mr. Dodfon, in this paper, has delivered a method of investigating the value of an annuity for life (secured by land) and the probability of survivorship, between two perfons of given ages, without having recourse to a fluxionary process. Art. 63. A letter to Mr. Peter Collinson, F. R. S. concerning the pheasant of Pennsylvania, and the otis minor. By Mr. George Edwards. The birds mentioned above have not before been properly defcribed, or delineated. There are plates of these birds added to the account, and those given by Mr. Edwards were properly coloured. Art. 64. A letter to Mr. Peter Collinfon, F. R. S. concerning a species of coralines. By Mr. John Ellis, F. R. S. In this paper Mr. Ellis observes, that from a great number of observations made on marine productions, it appears that many coralines, as well as corals, are composed of a great number of tubes, which proceed from animals; and as these tubes are made of different materials in different species, so are they disposed in variety of different forms. Some are united closely and compactly together, forming irregular ramifications like trees: others rise in tufts, like groupes of the tubular forts of plants, distinct from one another. Specimens of both these kinds are delineated on a copper-plate annexed to the article. He has also accurately delineated and described two curious pieces of Maltese coralline. 'The tubes,' says he, which are built by their inclosed animals, as they rife ** in height, greatly increase in diameter. The texture of their outside coat is formed of an ash-coloured earthy matter, of ' different fhades, in different ftrata, and closely united to an ' inner coat, which is of a tough, horny, transparent, and very smooth substance; the cavity, or inside of the tube, is perfectly round, tho' the animal is of a long compresled figure, like a leach extended. It appears from the marks of • its feet, on the infide of the tube, that it can turn itself freely about, and move up and down, the better to attack and se' cure its prey. ، • This scolopendra has two very curious and remarkable tentaculi, or arms, the left much larger than the right; these are doubly feathered; the number of feet on each side of the • body of this animal, exceeds one hundred and fifty.'-See more of this curious subject, in our mention of Mr. Ellis's book on corallines, &c. in the Review for March laft. Art.65. Obfervations on the late fevere cold weather. [In the winter 1754.] By William Arderon, F. R. S. and Henry Miles, D. D. F. R. S. Among several observations made on the coldness of the weather, Mr. Arderon tells us, that on the evening of December 30, he exposed in his garden an open glass, filled with ale, which froze even to the bottom, in a very odd manner; for the watery, or weaker parts, were frozen into plates of ice, sticking one to another by their edges, the more fpirituous parts remaining between them, in their interstices, unfrozen; which being drained off into another glass, the taste was almost as strong as brandy, with an high flavour of the hop. This method of concentrating vinous liquors by freezing, has been long fince published by that ingenious chemist, Dr. Stahl, and it seems strange that it has not yet been practised; for for it is evident, from his experiments, that the truly essential parts of wine, vinegar, malt-liquors, &c. may be thus obtained; the uses of which are too well known to need enumeration. Mr. Arderon says, that the part of the malt-liquor which remained uncondensed, had a high flavour of the hop; which is directly opposite to what Dr. Stahl observed, in a like experiment. Having,' says Dr. Stahl, by several condensa-' tions, reduced a full gallon of strong malt-liquor to the quantity of a pint and a half, the part that remained uncon' gealed was extremely rich; and for consistence and taste, far ' exceeded the famous double Brunswick mum. In point of • strength and spirituosity, it seemed perfectly aromatic, and nobly flavoured; a thing not found in common malt-liquors. And for consistency it resembled a dilute syrup, and with a • pleasing softness sheathed the acrimony of the spirit, and ' concealed the bitterness of the hop, which before was very ' confiderable.' Opufculum Chymico-phyfico-medicum. Art. 66. A letter from M. de l'Isle, of the royal academy of Sciences at Paris, to the rev. James Bradley, D. D. astronomer-. royal, &c. Translated from the French. This is a comparison between the observations made by Dr. Bradley at Greenwich, and those of M. de la Caille, at the cape of Good-hope, in order to determine the sun's horizontal parallax. From these observations, M. de l'Isle finds the horizontal parallax of Mars, 27" 11", and that of the fun 11" 20". Art. 67. Description of a piece of mechanism, contrived by James Ferguson, för exhibiting the time, duration, and quantity, of folar eclipses, in all places of the earth. This machine is well adapted for exhibiting the phænomena of solar eclipses; but as no adequate idea can be given of it without the figure, we must refer to the volume. 68. A letter from the rev. Henry Miles, D. D. F. R. S. to Mr. John Canton, F.R.S. concerning the late hard weather. Mr. Canton and Dr. Miles having each kept a register by thermometers, their near agreement was remarkable at noon and night, when the observations were made at the same hour; but on the 7th of February, a. m. Mr. Canton's thermometer was higher than the doctor's. 'This,' says Dr. Miles, • I attribute partly to your observation being made an hour ' later than mine, and after the fun had been above the horizon {three quarters of an hour: for I have found by long obfervation, Y 3 |