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common theory of this matter to take place before the bony substance is separated from the blood. Consequently the rapid alteration of colour produced ip the bones of farious animals by the administration of madder, and the disappearance of that colour on ceasing the use of that drug, ought to demonstrate a very rapid change, constantly occurring in the constituent parts of bones theinselves; a much more speedy one indeed than has been generally allowed to take place even among the soft parts. Mr. Gibson, however, supposes these effects much more plausibly explained, by taking into the account the attraction of serum for the colouring matter of madder, which he thinks sufficient to enable that fluid to deprive the bones of their acquired colour. His experiments, however, are not convincing, and he ought to have shewn, not that he could render pale, but that he could whiten dead bones by infusion in hot serù ñ. For it seems clear, that bones could never be whitened if this chemnical theory were just, since that obviously presupposes a superior attraction of the serum to that of the bones for the dye, but the very tinge of the bones themselves requires the reverse to be true. If the attraction of the serum be greatest, the bones could never become red; if that of the bones exceed, the bones, once red, could never become white again. .
In the fourth paper Dr. Bardsley considers the use and abuse of popular sports and exercises, in a manner suffici-.
ently able and entertaining; but without any peculiar pre· tensions, tó novelty in his arguments. Like many who have
preceded him in the same tract, he bestows his censures and malediction on all the methods of tormenting animals for amusement, and his applause on the whole admirers and practitioners of the noble science of pugilism. In the fifth paper, of which the Rev. Johnson Grant is the author, the subject of Reverie äs connected with literature; is discussed.
This gentleman, sometimes the observer and sometimes the - physician of the mind, seems, notwithstanding his efforts in · both these ways, to have added little to our knowledge of
reverie. But his essay does hin credit, as a very neat and sensible piece of composition.
Of the three. next papers Mr. Dalton is the author. They - freat of the different properties of elastic fluids as discovered by experiment, and of various extensions of the theory of the mutual penetrability of gases, which is well known to be entertained and most ingeniously supported by that gentleinah. In the first of these, which is entitled, “ An Experimental loquiry into the Proportions of the several elastic
Fluids constituting the Atmosphere,' three objects are considered ; vix, the weight of each simple atmosphere abstractedly, the relative weights of the different gases in a given volume of air at the earth's surface, and the proportion of the gases åt different elevations. These three objects of investigation, according to the theory of the chemical combination of the atmospheric gases, are one and the same; but, according to Nr. Dalton's view, extremely different. The first of them he conceives to be determined by finding the relative bulk of the component parts of any mass of common air, and a long discussion is entered into regarding the best method of separating the oxygenous from the azotic almospheres. In this we have noticed lille novelty, though we know how to value the experience of so accurate an observer as Mr. Dalton. The quantity of aqueous vapour is estimated, according to this gentleman's own experiments and theory, and the carbonic acid gas is found by the test of lime water to be much less than usually imagined. One remarkable and unexpected fact is slated, that little more than one per cent. of this gas would be detected in the air of a room in which two hundred people had breathed for two hours. We wish Mr. Dalton had also noted the quantity of oxygenous gas to be found, since, if no remarkable deficiency of that substance appeared, some important inferences might follow. We may observe, in our way, that Mr. Dalton retains the y where it ought to be in the chemical terms of Greek derivation ; and we are happy to express our satisfaction that some are yet left to oppose the rage of senseless innovation, which, regardless of etyinology, of harmony, and of elegance, attacks with a Gothic fury every remnant of Grecian origin, and annually clips and pares the nomenclature of eliemical science, after the fantastic fashion of the time, which is nevertheless sure to yield in its season to something still more extravagant than any thing before devised.
According to Mr. Dalton's statement, the weights of the different gases, constituting the atmosphere, are as follow:
. . Sinch. of Mercury.
44. . . . Carbonic acid gas.
. .09 :. .
- 30 . That is, the whole atmosphere supports a column of men. cúry of thirty inches, and each ingredient separately considered supports the share above stated. The proportional weights of these gases, in a given volume of air at the earth's
surface, are in their order per cent. 75.55, 23.32, 1.03, 0.10, the carbonic acid gas being thus reckoned only at a thousandth part of the whole. With regard to the proportions of the gases at different heights, we observe little satisfactory information, and Mr. Dalton seems. lo labour under an unnecessary difficulty of conceiving how a mechanical power may counteract a chemical one; whether that ever happens or not, is another question. ,
Mr. Dalton's second paper treats of the tendency of elastic fluids to diffusion through each other, which be proves to occur in every instance by most decisive experiments. The chief use which he is inclined to make of these curious facts is to support his own theory, which, in Mr. Dalton's opinion, tbey establish beyond controversy. But though these observations agree extremely well with the supposition of the mutual penetrability of the gases, they may equally well be reconciled with that of their chemical union.
Mr. Dalton's third paper relates to the absorption of elastic fluids by water and other liquids, which he supposes to be done in the following proportions“: either an equal bulk is absorbed, or else a part equal to one of the fractions, *, itTİT, &c. being the cubes of the reciprocals of the patural nunbers 1, 2, 3, &c. These quantities of gas are believed by Mr. D. to be mechanically inixed with the liquid, and not chemically combined with it. The greatest difficulty which this gentleman finds in bis hypothesis is, to explain why different gases observe different laws. After due consideration, however, we are inforıned that this difference most probably arises from the variation of the weight and number of the ultimate particles of ihe several gases ; and we have a tabulated result of experiments made to determine this question, which would be highly curious and interesting, if there were the least reason to believe in its accuracy. But though we are not let into the precise mode in which Mr. Dalton proceeded to this investigation, upon general principles we do not think bim in the right road. In fact the existence of these particles, of which we have hicard so much of late years, is in itself problematical, and the peculiarities of their sizes, shapes, or densities, wholly unknown. It is even a most doubtful point, whether there is ainongst them any original difference of specific gravity, or whellier the varying operation of caloric is not alone suf. ficient to account for all differences in this respect.
The ninth and teuth papers are by Mr. Gough : of these the first treats of a property possessed by Caoutchouc at a certain temperature, of communicating a sensation of heat tu the lips when drawn out upon them; and as it is proved
that this resin contracts in bulk when extended, the plena. menon observed by Mr. Gough is analogous to the heating of iron by haminering, and of gases by compression, and in like manner a resemblance may be noticed in all these bodies, in the diminution of their elasticity with that of their absoj lute caloric. · But Mr. Gough proceeds too rapidly when he infers that the capacity of the Caoutchouc for heat is diminished by its extension, a conclusion, no doubt, probable, and' justly deducible from Dr. Irvine's theory of heat, but not in this case immediately proved by experiment, as he imagines. In this paper, as in most others of the same author, we have to complain of a certain obscurity and perplexity of style. ..
In the next paper Mr. Gough enters into the consideration of Mr. Dalton's theory of gaseous mixtures, to the truth of which he is no convert, and which he labours hard to prove to be false on the principles of the mechapical philosophy. The parade of mathematical knowledge with which this is done, is surely very much misplaced, and the phenomena of cheinistry subunit with reluctance to the dominion of fuxionary increments and algebraic symbols. Mr. Gough's arguments upon the centre of gravity are just with regard to solid bodies, but we agree with Mr. Dalton that in the case of gases they are wholly irrelevant, and that if all the particies of two gases be nonelastic with
respect to each other, the whole' masses of gas are so like• wise.' Schmidt's experiments, on which Mr. Gough* laid :' considerable stress, are shewn by his opponent to have been
erroneously quoted by Mr. Kirwan, whose accuracy has in this detection suffered a dangerous injury. On the whole, we think Mr. Gough has said little to alter the opinion of the public on this subject. In this volume there is another paper by this gentleman, and one in answer, by Mr. Dalton, which are entirely confined to the consideration of the same subject.
There are besides some papers by Mr. Walker and Mr. - Holland, upon history and philosophy, of which it would be
difficult to make any remark at once good natured and energetic. To confess an honest truth, the Manchester society owes little of its celebrity to its moral or political public cations. These have in general risen to that happy state of mediocrity which shups at once the gratification of applause and the bitterness of censure. Few learned associations have gained much by thus invading the territories of the schools, and experience has now fairly demonstrated that he who searches for the meed of praise, will reach his aim : thousand times amid the pots of the chemists, the diagrams of the geometer, or the telescopes of the astronomer, ere one successful effort shall crown his hopes in the fairer regions of the belles-lettres.
ART. VII.-The Nature of Things; a Didactic Poem. Trans:
lated from the Latin of Titus Lucretius Carus, accompanied with the original Text, and illustrated with Notes, philological and explanatory, by John Alason Good. In two Volumes, 4to. Longman, 1805.
The charms of Lucretius cannot be expected to excite in an English reader that adıniration which has been liberally extended to translations of the more popular Roman poets. We have ever conceived that an undertaking of the nature before uş,even in a compressed form, would never meet with the reward due to the labour requisite to its completion. But our astonishment was raised when we contemplated the ' Poem of Lucretius? extended through two enormous quartos, and we wondered considerably at the boldness of the author, while there may not be wanting some, who may also stare at the boldness of the reader. If in the perusal we have not been thoroughly recompensed for our diligence, we have occasionally felt a gratification which it shall be our aim to cominunicate to our readers. We have not unfrequently been highly pleased with the poetry, as well as with the taste and good sense contained in some of the notes; and we have throughout admired the tenaciqus enthusiasm with which Mr. Good detends every tenet and every foible of his original. We have smiled perhaps, and have disapproved ; nor shall we hesitate to perform the most disagreeable part of our office in the exposure and delection of ersors. When our judgment is unfavourable, we shall not deal in general severity, but substantiate every objection by a corresponding reference.
The blaze and display of multifarious learning in the notes, is calculated, we think, more to dazzle than to iinprove. Mr. Good has catered for the public, and presented it with a most substantial dish. It is an olla podrida or omnium, consisting of scraps from · Hebrew, Greek, Latin, French, Italian, German, Spanish, Portugueze, and English,' (let us breathe for a moment) and' from Mr. Good's love of Asiatic poetry,' he leads us sometimes into the sister languages of Arabia and Persia.' But before we enter, as Mr. Good would call it, into this! chaotic' and 'tesselated'' amalgamation of the omng scibile, we will venture