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toms, indeed, which he betrays, are the ordinary indications of violent pique: but some people have an odd way of shewing their composure. Pope said of the pamphlets written against him," these things are my diversion"; and possibly this present article may be to Dr. R. " as good as a dose of hartshorn." Despairing, perhaps, of bending living mathematicians to his opinion, the Professor has moved Bishop Horsley from the dead to his assistance. We readily allow that Dr. H. possessed various attainments, and great vigour of mind but, since we are thus compelled to speak of him, we shall not grant that he was a mathematician of the first rate. He undertook a Commentary on Newton without the due requisites, of which the commentary itself is a proof; and, if we were to select an instance in which, under the pomp of a learned language, he endeavours to conceal his insufficiency, it should be the passage quoted by Dr. R.: " Si hoc vere dictum sit, nescio qui fieri possit, ut alius sit punctorum æquinoctialium motus, à vi solis oriundus, quam calculi Newtoniani suadent. Quem tamen longé alium invenerunt viri permagni Eulerus et Simpsonus nostras ; quos velim lector consulas; ipse nil definio." This is rather sounding and empty from one whose special business it was to explain difficulties and settle agitated questions.

malice ?

Dr. Robertson repeatedly attributes to us motives that are quite foreign to our minds. Why should he excite our But the chagrin of censured authors is no rare phænomenon. If the Doctor will resume his boasted composure, he may conjecture, among the possibilities of explanation that present themselves, that a disrelish for his compositions may possibly originate from something else than profound ignorance, or deep malignity, or unaccountable prejudice. We may have done that which we think we have done, merely our duty-which duty enjoins us to detect plagiarism, and to crush nonsense bursting and bustling into existence, before it acquires an activity that may be troublesome to the public. Let not the Professor hope by the terrible chastisement of his replies to prevent us from doing this duty. As Dionysius formerly sent Philoxenus to the quarries to mend bis judgment, so like the poet, rather than commend Dr. R.'s papers, we should cry, "Take us back to the Quarries."

To conclude :-we apprehend that our former assertions of the similarity of Dr. R.'s processes and of those of Simpson have been shewn not to be, in the least, invalidated by the present reply; while the sameness of Euler's and of Dr. R.'s proof of the binomial, not solely in principle but in every part, has been evinced almost to demonstration. Of men who still assert the proofs to be dissimilar, yet unwittingly establish

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their similarity, what rule of decorum or of criticism enjoins us to speak modestly* and to judge hesitatingly? We should plainly declare ourselves unfit for our situation, by falling into such ludicrous extremes of squeamishness and circumspection.

Dr. Robertson has chosen to mix with his remarks on us some strictures on other critics, and some unauthorized allusions to names which are "out of the record." We never interfere with disputes to which we are not parties, nor countenance a propensity to undue personalities even by exposing its mistakes.

ART. IV. Philosophical Transactions of the Royal Society of London, for the Year 1807. Part II. 4to. 15s. 6d. sewed. G. and

V

W. Nicol.

VARIOUS circumstances have concurred to delay, for a few months, our account of the concluding part of the labours of the Royal Society for the last year: but we shall now endeavour to execute our office in reporting them to our readers; and we shall still hope to discharge it before the appearance of their first publication for the present season shall reproach us for our tardiness.-We shall begin with the papers relative to

NATURAL PHILOSOPHY, MEDICINE, CHEMISTRY, &c.

On Fairy Rings, by W. H. Wollaston, M.D. Sec. R.S.-We learn from this essay that Dr. Wollaston's opinion respecting the origin of those circles of dark green grass, which are usually I called Fairy-rings, is that they are produced by the growth of some particular kinds of fungi, which spring up from a central point, but, being afterward unable to find their proper pabulum in the soil in which they have already grown, naturally form a circle around it. This circle becomes each year more widely extended; and in consequence of the quantity of decayed vegetable matter which the plants leave behind them, a ring of peculiarly luxuriant grass is produced. Dr. Withering ascribed these rings to a similar cause, but supposed them to be formed by one species of fungus only, whereas Dr. Wollaston has observed fairy-rings produced by four kinds of fungi.

* The excellent precept, which Dr. R. has prefixed to his pamphlet, he has by matilation robbed of half its efficacy. It ough to stand thus: "Sed modeste et circumspecto judicio de tantis viris pronunciandum est, ne, quod plerisque accidit, damnent quod non intelligunt,"

Observations

Observations on the Structure of the Stomachs of different Animals, with a View to elucidate the Process of con erting animal and vegetable Substances into Chyle, by Ev. Home, Esq. F.R.S.In some late researches on the stomachs of ruminating animals, Mr. Home had been led to observe that the fourth cavity, which may be considered as the proper digestive organ, was always divided into two portions, possessed of a different struc ture, and adapted for performing different offices; the first being a preparatory process, while the second alone served for the purpose of converting the food into chyle. He was induced by this observation to examine the stomachs of other animals; and not withstanding the dissimilar arrangement of their parts, and the many peculiarities of form which they. presented, it was found that this all had a general analogy on this point, and that in all of them might be detected the two structures which he had perceived in ruminating animals. The object of the present paper is to trace this affinity through all the varieties of stomachs, beginning with those which most nearly resemble the ruminating, and proceeding to such as are entirely carnivorous.

After some preliminary observations, the author enters on his descriptions; he begins with the Turkey and then gives. an account of the stomachs of the Cod, the Hare, the Beaver, the Dormouse, the Water-Rat, the common Rat, the Horse, the Ass, the Kanguroo, the Hog, the Pecari, the Elephant, the Mole, the Stoat, the Armadillo, the human subject, the Lynx, the Vampyre Bat, the long-eared Bat, the Hawk, the Cormorant, the Viper, the Turtle, the Frog, and the blue Shark. These descriptions, though concise, are sufficiently clear, and are accompanied by accurate and well executed engravings. The general result of the observations is that, in all these animals, notwithstanding the great diversity in shape and configuration, the proper digestive organ is divided into two parts, which, from their situation, may be denominated the cardiac and pyloric pertions. This division is more or less obvious in the different kinds of animals; in some, it is clearly marked by strong membranous bands, and is of course equally visible in all states of the organ: whereas in others, particularly in the human subject, the two portions are separated merely by a muscular contraction, and can only be detected in particular states of the organ. We shall quote this part of Mr. Home's paper:

The human stomach, when examined recently after death, puts on appearances, that have not been noticed, which make the present description, and the drawing that accompanies it, necessary to explain these circumstances. It is occasionally divided by a muscular

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contraction into two portions; these are in shape, and relative size, sometimes similar to those of the beaver, at others to those of the horse. When its internal surface is accurately examined under the most favourable circumstances, the orifices of the œsophageal glands are distinctly seen in different parts, but more numerous just above where the cuticle terminates at the orifice of the cardia. Immediately within the cavity of the stomach, there are clusters of glands, exceedingly small and pellucid, crowded on one another, spread over the internal membrane of the small curvature for several inches in extent, but no where else. To have a distinct view of them requires the use of a magnifying glass; but when once observed, they are seen with the naked eye. The cardiac portion has an uniform surface, but towards the pylorus there is a more minute structure, very much resembling the appearance of a tesselated pavement, composed of very small portions of different forms.'

Mr. H. principally confines himself in this memoir to anatomical description, and declines any discussion on the theory of digestion but he makes some general deductions from the facts collected, which are principally illustrative of the gradations that may be traced in the different classes of animals. In the stomachs of all of them, the peculiar structure of each division of that organ appears destined for the two purposes, first of preparing the food, and secondly of the actual digestion of it. The cardiac cavity is furnished with numerous glands, from which is poured out a peculiar fluid that softens and partly dissolves the aliment: but it never undergoes the complete change until it arrives at the pyloric cavity.

Our readers are probably aware that some physiologists of eminence have denied that the process of chylification is ever completed in the stomach itself: but the affirmative is maintained by Mr. Home, who appears to have adopted it principally in consequence of some experiments that were performed by Mr. Hunter. That gentleman's remarks, however, do not convey to us exactly the same impression which they seem to have made on the present writer. Mr. Hunter stated that the food was more and more digested as it advanced towards the pylorus, and that "just within" the pylorus it was converted into chyle.-Any opinion on this point, however, does not affect the general merit of Mr. Home's paper, which we consider as a very valuable collection of observations.

On the Oeconomy of Bees. In a Letter from T. A. Knight, Esq., F.R.S. to Sir Jos. Banks, Bart., P.R.S.- In the course of his interesting experiments on vegetable physiology, Mr. Knight has been led to attend to the habits and economy of bees, and he presents us in this paper with the results of his investigations. It has been generally supposed that each indi

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vidual hive forms a complete republic within itself, totally unconnected with all other collections of bees: but Mr. K. has not unfrequently remarked that a kind of intercourse takes place between two hives, which continued for a few days, but seemed always to end in violent hostility. Another circumstance which he has observed is that, before a new swarm fixes on its future habitation, a few bees are sent out as scouts, to discover a suitable spot; and when the colony leaves the parent-hive, they bend their course immediately to the place which they appear to have previously selected. These and other similar circumstances, which we believe are not now noticed for the first time, lead us to conclude that these animals are not only possessed of a remarkable share of sagacity, but that they must have a mode of conveying information to each other with a considerable degree of accuracy. Mr. Knight, indeed, supposes that they differ from other brutes in possessing, as he expresses it, not only a language of passion, but a language of ideas: but we imagine that the faculties of bees differ more in degree, than in kind; from those of other animals.

A new Eudiometer, accompanied with Experiments, elucidating its Application, by William Haseldine Pepys, Esq.--This gentleman begins by giving a short account of some of the instruments which had been previously invented for ascertaining the quantity of oxygen in a given portion of air, and then proceeds to describe his own contrivance for this purpose. It consists of a graduated measure, an elastic gum bottle, and a graduated tube. The air under examination being introduced into the measure, the bottle is filled with the fluid which is intended to act on the air, and is then pressed up into it. The measure is graduated so as to mark the hundredth parts of a cubic inch; and for more minute divisions a small graduated tube is employed, which, by a peculiar contrivance, is introduced within the measure, and is so constructed as to denote the thousandth parts of an inch.-We found a little difficulty in understanding Mr. Pepy's description of his apparatus, in consequence of some of the references to the plates being, as we apprehend, inaccurately marked.

When Mr. P. operates on air which contains oxygen, he employs for its absorption the green sulphate of iron impreg Inated with nitrous gas. For examining the purity of nitrous gas, the green sulphate or muriate of iron is employed; for carbonic acid gas, barytic or lime water; and for sulphurated hydrogenous gas, a solution of the nitrate of silver. The nitrate of silver promises to be an useful agent in eudiometry, since, by employing it hot, we are enabled to separate com

pletely

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