The LONDON MAGAZINE: A る Or, GENTLEMAN's Monthly Intelligencer For OCTOBER, 1755. To be Continued. Price Six Pence each Morth) Containing, (Greater Variety, and more in Quantity, than any Monthly Book of the fame Price.) I. New Theory of Light and Colours. II. Nature and Produce of Beetles. V. -- - of our Minifters abroad. VI. VII. American Governors. the Commiffioners of Trade, &c. VIII. Mathematical Questions and Solutions. IX. Utility of Broad-Wheels. X. Life of Sir John Suckling. XI. The JOURNAL of a Learned and Political CLUB, &c. continued: Containing the SPEECHES of Pofthumus Co-minius, and Manius Valerius on the vot. ing of Copyholders as Elections. XII. Of the War, Subfidies and Taxes. XIII. Of Infuring Foreign Ships. XIV. Of Knowledge and Ignorance. XV. Character of Cramwell and his Club. XVI. Terms in Carving. XVII. Strictures on the English Language. XVIII. Diftrefs of a fuffering Family. XIX. Matlock Bath defcribed. XX. Letter from Conftantinople. XXI. Large Calculus in a Mare. XXII. Of Archimedes's burning Speculum. XXIII. Account of the British America. XXIV. A dreadful Maffacre. XXV. Alliance of Church and State defended. XXVI. Authors methodical Madmen. XXVII. Method of Fowling in Norway. XXVIII. Fondnefs tor Animals fatirized. XXIX, POETRY, To the D-ke de M-x; Boasting Mule; True Concord; Song on Mifs Ifabella; on a Lady's Picture; Prayer to Venus; on Lady T-'s Chinefe Houfe; True-Blue, a Song; Ode to the 17th of Auguft; Sonnet ; Chit-Chat; wrote in Forbes's Works; the dying General; the Lover's Invitation; Epigrams; Fair Delia, a Song fet to Muick, and a new Country-Dance. XXX. The MONTHLY CHRONOLOGER : Tranfactions of our Sea Forces and Advices from America; Warlike Preparati ons; Court-Martial; Irish Medal; Account of the Cherokees; Letter from Sır Alexander Cuming; Seffions at the OldBailey, Fires, &c. &c. &c. XXXI. Promotions; Marriages and Eirths; XXXII. Plays acted at the Theatres. XXXIV. A Catalogue of Books. XXXV. Prices of Stocks for each Day. With a Head of Sir JOHN SUCKLING; a Pspect of MATLOCK-BATH, and a View of the MULTUM IN PARVO. LONDON: Printed for R. BALDWIN, at the Rofe in Pater-Noller-Row; A CONTENT S. New theory of light and colours 459 Nature and product of beetles ibid. Of the perspiration of vegetables 460 An authentick lift of the French navy 461 Lift of his majesty's minifters abroad 462 -the American governors ibid. --the commiffioners of trade, &c. ibid. Mathematical questions and solution ibid. 464 Utility of broad wheels demonftrated 463 Life of Sir John Suckling 464 The JOURNAL of a Learned and Political CLUB, &c. continued 465-472 SPEECH Of Pofthumius Cominius on the voting of copyholders at elections 465 -468 The time improper to difcufs the question 465 And the method for determining it 466 Agreeing to the motion would be unjust 467 A dreadful maffacre Revenged on the Indians 486 Alliance between church and state de- Authors methodical madmen Methods of fowling in Norway ibid. 487 ibid. 488 489 ibid. Vifit to Mrs. Penelope Doat's nursery 490 ibid. And fet in a ridiculous light 491 Extraordinary card metlage ibid. POETRY. Fair Delia, a song set to mufick Ecclefiaftical preferments Promotions civil and military Perfons declared bankrupts 500 ibid. 501 ibid. 502 ibid. 503 Prices of stocks and grain; wind, weather 504 Monthly bill of mortality ibid. Plays, &c. acted at the theatres Of the burning the fleet of Marcellus 482 By Archemedes's burning fpeculum ibid. Father Kircher's experiment thereon ibid. And problem 483 Account of the plantations continued ibid. Virginians oppreffed by James 1. 434 Good regulations in the colony ibid. Mr. A. B. of Ongar, fhall be obliged; the mathematical pieces lately received shall be inferted in due time, and the advice of Vellum followed. The other poem from our old correfpondent R. D. is ready to be returned, for as it has been fent to another Collection, we cannot infert it in ours. Tho' 15 pieces of poetry this month are originals, we are fill in arrear to many kind correfpondents, who fhall be gratified in their turns, and may easily perceive our firiët impartiality by the three laft months: Irdeed their productions do bonour to our Magazine. A DVERTISEMENT. All Sorts of ALMANACKS for the Year 1756, will be published together at STATIONERS HALL, on Tuesday, November 18, 1755 THE LONDON MAGAZINE. OCTOBER, A new Theory of LIGHT and COLOURS. VERY one knows, that the famous Sir Ifaac Newton explained the phenomena of light and colours by fuppofing, that the rays of light A E themselves were of different colours, fome of which are generally reflected from any object more copiously than any of the reft; and that the object always appears to be of the colour of thofe rays which are moft copiously reflected from it, except the colour of white, which is communi cated by an object from whence all the different forts of rays are equally reflected, and the colour of black, which is communicated by an object from whence no rays at all are reflected to the eye. But Mr. Euler of the royal academy at Berlin, upon confidering the effect produced by looking glaffes, concluded, that the rays of light reflected from any furface ought to make us fee the luminous body from whence thofe rays originally proceeded, and not the furface itfelf, therefore he fuppofes, that light is not produced by a continual emanation of rays of light from the fun, by which he would at laft be quite exhaufted; but that it proceeds from a certain fort of 1755. that the different colours exhibited by very thin glass plates, or by foap-bubbles, proceed from the vibratory motion excited by the rays of light in those plates or bubbles, which must be thin to a certain degree, in order to be fufceptible of these vibrations, and these vibrations being again communicated by them to the ether, in proportion to the different degrees of thickness in the parts of the plate or bubble, produce in us the different fenfations which we call red, green, blue, &c. Mr. Euler confirms this hypothefis by feveral other experiments; and it is likewife in part adopted by M. l'Abbé Nollet, famous at Paris for his lectures on expeBrimental philofophy; for by many expe riments he has endeavoured to prove, that light is a moft fubtil fluid by which all bodies are pervaded, as well as furrounded, and which becomes fenfible to us by being put in motion by inflamed bodies or otherwife; but then he embraces Sir Ifaac Newton's opinion as to the rays of light being of different colours, and producing in us the idea of that colour which is moft copiously reflected from any object. D vibration communicated by him to what From hence this gentleman concludes, A curious Remark upon the Nature and Pro duction of these Infects called BEETLES. T having been often obferved that, if at certain feasons of the year, a mole, or other fmall animal, be killed, and left above ground, the body difappears in a very few days, more or lefs according to the feafon of the year, and the nature of the ground. This phenomenon excited the curiofity of Mr. Gleditfch, of the royal academy of fciences at Berlin, to endeavour to find out the cause of this fudden and extraordinary difappearance. For this purpofe, in the month of May, he killed a mole, and left it above ground in his garden, where there was a foft, black, and moift earth. In two days the body as ufual difappeared, but a little fpot of earth near the place appearing to Mmm 2 have 4 460 Of the Perfpiration of VEGETABLES, have been fresh turned up, a fearch was Erveral curious Obfervations upon the PER- tables. COME years fince Mr. Guettard laid in the day-time. 3. That in the daytime they perfpire more in the fun than in the shade, even tho' the latter be the warmest fituation. From hence perhaps arifes the rapid growth of vegetables under bell-glailes; for the rays of the fun being much intercepted by the bell, the A perfpiration is thereby diminished. For the fame reafon, without doubt, thofe fruits which are not too much expofed to the rays of the fun, grow to be the biggeft; and fo likewife thofe paper bags which the bunches of grapes are put into, not only protect them from birds and flies, but alfo increafe their beauty. By this we may perceive the ufe of the leaves, which is to be a fhade for the fruit; and we may likewife fee the reafon why dark and cloudy weather is beft for the fruit after it begins to ripen, because fuch weather diminishes the perfpiration, and thereby increases the bulk of the fruit, There are we find fome trees which lofe their leaves much fooner than others of the fame kind, tho' both growing in the fame fort of ground; the reafon of which certainly is, because the former happen to be by their fituation more expofed to the fun, which makes them perspire more abundantly. The 4th obfervation was, that perfpiration proceeds chiefly from the leaves. The 5th, that the fuperior fur face of the leaves, being more exposed to the fun, is thereby made to perfpire more D before the royal accademy of fciences than the inferior. The 6th, that thofe vegetables which have thick leaves, and fruit of a juicy fubftance, perfpire the leaft; and therefore do not fland much in need of being watered. The 7th, that perfpiration grows much lefs towards the winter than it is in the fummer. And the 8th, that the liquors produced by perfpiration, from vegetables of quite different kinds, are nevertheless perfectly the fame, having all the fame infipidity, and no way differing from common water in clearness, tafte, fmell, or weight. Mr. Guettard made thefe experiments by means of a glass-bail or bottle of a foot diameter, which, befide a neck in days, in the month of August, produces, F the usual form, had two arms or necks oppofite to each other, and placed at the two extremities of the diameter, perpendicular to the line of the neck; being a veffel of that fort which by chymists is called Glauber's recipient. The branch of the tree or vegetable was introduced thro' the neck of this glass-ball, and one of the arms being fet upright, was well corked, whilst the other was made to enter into a bottle which was buried in the earth quite up to the neck, and clofely luted, The 1755. LIST of the FRENCH NAVY. Names. A Le Palmier The fame gentleman has lately communicated an account of feveral new experiments he has made, from whence he has deduced the following obfervations, ift. That the perfpiration of vegetables increafes or decreases exactly in proportion as the heat of the fun increafes or decreases. 2. That their perfpiration does not increase in proportion to the quantity of rain upon the ground: On the contrary, when the fun begins to shine after a heavy rain, the perfpiration of vegetabies is never the first day at the greatest height. 3. That the leaves do not draw fo much moisture from the air as one would be apt to believe; for an orange tree inclofed in a glass globe perfpired B daily near to the weight of all its leaves, and did not feem to fuffer in the leaft by its imprisonment. 4. That in the shade the perfpiration diminishes in proportion to the deepness of the fhade. From hence it is that vegetables grow white in a cellar; for as they do not there perfpire, their veficles are made to fwell by that water which is confined in them, and by this means they acquire a double advantage, that of becoming more white, and that of becoming more delicate. 5. That the branches perfpire lefs than the leaves. 6. That the flowers perfpire likewise less than the leaves, in the proportion of to 5. 7. That the fruit perfpire still lefs, efpecially thofe that are of a juicy kind. 8. That the evergreens perfpire almost nothing in the winter, in comparifon with what they do in the fummer, and their perspiration is at all times less than that of any other trees. To conclude, what is worth the attention of all botanifts who incline to repeat or to push thefe experiments, is, that the greater or E leffer tranfparency of the glafs veffel they make ufe of for their experiments, may occafion a very confiderable difference. A Lift of the FRENCH NAVY, 1755. Second Rates. C L'Hector Le Nortumberland Le Triton L'Orpheus Le Glorieux Le St. Philip Le Bienfaifant La Medee Le Temeraire 74 74 Le Couragieux 74 74 Le Fleuriffant 64 Le Protee L'Hercule 64 580 64 580 64 580 64 580 64 580 64 580 64 580 64 580 64 580 64 580 64 580 Le Vaillant 64 586 Le Dragon 64 580 Men. Le St. Michel 64 580 Le Boree 64 580 L'Ecumant 64 580 Le Foudroyant 80 700 Le Solide 64 580 64 580 64 580 64 580 L'Ocean 64 580 60 Le Tonant 580 Third Rates. 580 L'Alcide, taken 74 580 G Le Brillant 60 580 400 L'Intrepid 74 La Sceptre Le Conquerant |