the publication of fimilar experiments by other labourers in the fame field of philofophical investigation. "The application", Mr. L. fays, " of a coat of pigment to a metallic furface, inftead of retarding the effect, almost doubles its difcharge of heat. This fact, equally curious and important, is moft contrary to the prevalent notions, and feems not to have been hitherto obferved." P. 269. And, a little further on, he adds, Nay, a tin canister, filled with hot water, will cool confiderably fafter after it is covered with flannel, and would require the farther addition of one or two folds to make it cool at the fame rate as before; the profufe energy of its unmetallic furface being then compenfated by the retardation arifing from the thicknefs of the spongy mafs." P. 270. Having inveftigated the cooling powers, which currents of air of different velocities are likely to have, Mr. L. towards the end of the laft-mentioned chapter, proposes a new and fimple fort of anemometer; viz. a fimple thermometer heated - by the application of the human hand, and then exposed to the current of air; for by observing the time of its refrigeration through a given number of degrees, the velocity of the current of air may be estimated by means of a rule which is given in page 285. We are inclined however to fufpect, that, as various circumftances concur towards the production of the effect, this anemometer is not likely to prove very accurate. The fixteenth, feventeenth, and eighteenth chapters contain further inveftigations of the mode by which a cold ftream of air or water, cools the bodies upon which it falls; together with feveral other experiments, remarks, and calculations. concerning refrigeration. The greatest number of thofe experiments were made by inclofing a canifter, or tin vessel, in another canister of a fize a little larger, and this in another ftill larger, &c. a fmall fpace intervening between them, The innermoft of thofe veffels was filled with hot water, and a thermometer was fixed in it. The experiments were divid ed into three fets; viz. 1. when the furface of the internal canifter and its feveral cafes were metallic; 2. when those furfaces were all painted, or confifted of glafs; and 3. when they were compofed partially of both forts: and the rate of cooling was examined in all thofe cafes. The nineteenth chapter defcribes, in a very particular manner, the photometer, or meafurer of the intenfities of light, invented by Mr. Leflie. This inftrument is nothing more than than a differential thermometer, fuch as has been described before, having one ball only painted black; for when this inftrument is exposed to the light, the black ball, by absorbing more light is thereby heated more than the oppofite ball, and of courfe depreffes the fluid in the graduated ftem. This effect is proportionate to the intensity of the light to which the inftrument is exposed. The various application or ufes of this photometer are mentioned in the twentieth chapter, where it is shown, that with it may be measured the intenfities of light in every poffible cafe; i. e. the enquirer may be enabled to determine the quantities of light of different feafons, of different luminaries, of the different times of the day; alfo the tranfparency of diaphanous bodies, the reflecting powers of different fubftances, &c. Towards the end of the fame chapter, Mr. L. fhows how the fenfibility of his photometer may be increased to such a degree as perhaps to be affected even by the feeble light of the moon. The important experiments relative to the conducting power of air, meaning its power of conducting heat, in different ftates of rarefaction; and likewife the condu&ing powers of other gafes, are described in the twenty-first chapter, which is the laft of the work. Thofe experiments were performed by fixing the photometer within the glafs receiver of the air pump, and applying a hot body to it under different states of rarefaction. The conducting power of air was found to diminish with its rarefaction; but, when the fucceffive denfities of the air were in geometrical progreffion, the decreasing conducting powers did not form a progreffion quite regular. Mr. L. endeavours, with much ingenuity, to trace the nature of this decrease of conducting power; but, with refpect to those particulars, we must refer our readers to the work itself. "Whatever", Mr. L. fays, " has the property of dilating the air, has likewife a tendency to deprefs its power of abftracting heat. The various elaftic vapours, in mixing with the atmospheric fluid communicate their peculiar expanfive force, and feem by that union to occafion a proportional diminution of its conducting quality. The influence of humidity is vifible, but the more volatile fubftances have a marked effect.” P. 281. And, in p. 483, he says, "The permanent gafes differ as much from common air, perhaps, by their difpofition to conduct heat, as by their denfity or other pro Hh BRIT. CRIT. VOL. XXV. APRIL, 1805. perties. perties. The azotic and the oxygenous, indeed, feem to poffefs it nearly in the fame degree. But carbonic gas abftracts the heat from a vitreous furface about an eighth part flower, and from a surface of metal one-fourth flower, than common air. By progreffive rarefaction, that property is alfo reduced on a fimilar fcale. Hydrogenous gas, however, is the moft diftinguished by its affection for heat, which it conducts with unusual energy." Thus we have endeavoured to give our readers fome idea of the contents of a work, which highly deferves the atten tion of the philofophical world. Rich in new and useful facts, as well as in proper remarks, and judicious obfervations; it furnishes abundant matter for philofophical invefti gation, and opens new paths into the labyrinth of natural energies and operations. We are by no means fatisfied with all its hypothetical part; and it might be wifhed that the whole were digefted into a more methodical order, with a fimplification of the calculations, and other ufeful improvements. But we trust that, in a future edition, Mr. L. will endeavour to render this work as perfect as the nature of the fubject may admit. BRITISH CATALOGUE. POETRY. ART. 14. The Pleasures of Compofition, a Poem, in two Parts. Part I. 8vo. 60 pp. 2s. 6d. Hatchard. 1804. This unfinished Poem is attributed to a gentleman, whofe writings have more than once received the public approbation, Mr. Eyles Irwin. A cultivated taste, and an ardent zeal, for the polite arts, appear in the prefent compofition; which, as a poem, is chiefly defective from a degree of obscurity, fuch as a further attention to the ftyle and expreffion might perhaps remove. The following lines, for instance, though good in cadence, are extremely enigmatical: "By moderns held a monumental art, A nation's tribute to her CHATHAM's fhrine: Hence Hence thro' the abbey's venerable ailes, In the beginning of this paffage, the poet means, that the ancient patriot had a statue fo early, that Cæfar fell before the figure of his rival Pompey, but that moderns wait for pofthumous honour of this kind, as in the cafe of Lord Chatham. This is the general idea; but it is by no means fufficiently developed; and what is intended by the concluding line, we have not been able even to conjecture. This is only one paffage out of feveral, to which a fimilar objection might be made. See particularly 1. 236, in which a whole hiftory is alluded to, without the least direction to the reader, except the note. Compofition is invoked in the beginning as a perfon; we then find that the includes Sculpture, both of ftatues and medals, Architecture, Painting, Mufic, and Poetry. Yet all of thefe are alfo feparately perfonified; and Sculpture, we fee in the paffage juft cited, is once an orb with fetting rays. The fubject of the Poem is, in fact, rather the history and merits of compofition than the pleafures of it: unless the author means (which we rather fufpect) the pleasure which the com-' pofitions of one man give to others, and this his title by no means expreffes. He is fometimes incorrect in his accents; as folácer, ver. 333, and óbdurate, ver. 456. The Poem contains only 458 lines; the reft of the book confifts of notes. Should the author proceed in his plan, it will be neceffary for him to revise this first part with much care; taking the advice of competent judges on the fubject. The plan wants improving, in feveral inftances, as well as the expreffion. We fincerely wifh, for the fake of the author, to fee it laboured into a more perfect form. ART. 15. The Sorrows of Seduction; with other Poems. 12mo. 3s. 6d. Longman and Co. 1805.. This little volume, which, as the author fays, paffed from himself immediately to his publifhers, without any examination on the part of a friend, exhibits great elegance of tafte, and warmth of feeling. The first Poem, on Seduction, though unfortunately the fubject is trite, is well managed, and has many pathetic and beautiful paffages. We have only room for a fpecimen of the author's lighter effufions. 66 EARLY SPRING. With timid air, and cautious foot, Young Spring, With Flora fair and Zephyr on the wing, In bending attitude with lift'ning ear, She darts her glance along the mofs-brown vale, Should rude affail her with his withering gale. Oft as the hears him murmur in the dell, Young Genius, thus by fearful breaft betrayed, ART. 16. The Minstrel; or, the Progress of Genius. With some other This little volume, in its poetical part, offers only the ufual collection of Dr. Beattie's compofitions; and very excellent reasons are offered (in p. xiii.) againft bringing forward to public notice, those poems which the author's own judgment had determined him to fupprefs. The Life of Dr. Beattie, the only novelty in the book, as being the production of the biographer of the British Effayifts, will de fervedly attract attention. The foundness of Mr. Chalmers's opi nions, which we have always admired, appears confpicuoufly in the following paffage, which is alfo very happily expreffed. It is occafioned by the defence which Dr. Beattie thought it neceffary to make for his own warmth, in fome part of the Effay on Truth. "The mode of treating the writings of infidels, like every other fpecies of controverfy, muft partake of the varieties of human temper, and temper is frequently obferved to take a freer range in the clofet than in fociety. I am willing to allow, therefore, that the author of the Effay on Truth" is warm when compared to fome who have written against Hume and the fceptical philofophers. Dr. Campbell has been praised for his urbanity to Hume, and for carrying on a ref pectful correfpondence with a man whofe pernicious opinions he thought it his duty to expofe and confute. Dr. Campbell was beyond all doubt fincere, but he was not indignant. The question, therefore, may to fome appear of difficult folution, in what manner the profeffed enemy of Chriftianity is to be treated? This has been frequently propofed, but it has not been fatisfactorily anfwered. All will acknowledge that there are certain rules of good manners, the breach of which no controverfy can justify; but the mere admiffion of this will probably be thought infufficient. There are men likewife who think that we ought to argue for the evidences of religion and the foundations of human happiness, with as much coolness as if the conteft related to the niceties of grammar, or the dates of history; but neither will this be admitted as a confiftent principle. In all difputes, the warmth, the zeal, the exertions, muft rife in proportion to the value of the object contended for; and if the exuberance of the affections be ever pardonable, it must furely be in the cafe of a man who endeavours to rescue from fophiftry and perverfion doctrines of eternal importance; and who fees, or thinks he fees, the religion, morals, and * See Brit. Crit, vol. xxiii. P. 548. happiness |