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charger a second and third time, we had kept it in its first fitua. tion for triple the almost momentary space of time, the effect would bave been the same.
Notwithstanding these experiments are liable to such weighty. objections, the conclusions which they afford, in certain inftances, may be regarded at least as approximations that possess fome value. It appears that the striking distance between two points is three times greater than that between a point and a. plane, and ten times greater than that between two planes. When balls are used, this limit extends with the increase of their diameters and diminution of the charge. A Mock paffes, more readily in water from one plane to another, than from a point to a plane ; 'exactly the reverse of what takes place in air. The conducting property of water is improved by the addition of common salt or nitre, and especially of acids. The fulphuric acid is so eminently a conductor of electricity as to fur.' pass even charcoal, and to rank next to the metals. A change of temperature, however, greatly affects the results; insomuch that boiling water exceeds sulphuric acid in the facility with. which it transmits the electric Auid. . The same property, though in a less degree, is manifest in hot oils. Alcohol is ina ferior to water as a conductor, and the different oils and æther follow. Of the solid imperfect conductors or electrics, the or der is this ;-bees-wax, sulphur, plate glass, and hell-lac. Hence Mr. Morgan takes occasion. (o recommend shell-lac as: the best ingredient in all cases for insulation. The different gases conduct electricity nearly in proportion to their rarity, the hydrogenous being by far the most remarkable. With regard to the metals, our author concludes that they possess equal, or almost equal, conducting powers. , In this nice investigation, the imperfection of his mode of experimenting is most fensibly felt. That mercury is vastly inferior to the other me. tals as a conductor, it requires no profound observation to svinge ;-and these metals differ as widely in this as in the rest of their properties. Not to secur to other proofs of this afiertion, we may refer to the late experiments on animal elec. tricity. Mr. Morgan remarks, indeed, that the electric Auid meets with some reliance in its pallage through metallic conductors, when they are particularly circumstanced. Thus, the discharge would rather pass through 7-85hs of an inch of air and a wire one foot long and 12 inch in diameter, than through a wire alone 12 yards in length 1-25th of an inch in diameter; which difference was not perceptible when the small wire was coiled up and placed in the circuit. The case of interrupted conductors is more remarkable; and Mr, Morgan
could not fail to observe the prominent contrast in that respect, between a chain and a wire of the fame length.
[To be concluded next month.]
Art. VI. The Thymbriad, (from Xenophon's Cyropædia.) Ву
Lady Burrell. 8vo. pp. 154. 6s. Boards. Leigh and Sotheby.
1794 Art. VII. Télemathu. By Lady Burrell. 8vo. pp. 78. 49.
Boards. Leigh and Sotheby. 1794. THOUGH these two poems are publifhed separately we give
our opinion of them jointly, because they are of the same character. They are both grounded on well-known stories; both amplify the original incidents and sentiments, in order to afford an opportunity of displaying the poet's descriptive powers; both express at large, in let speeches, the emotions and passions respectively belonging to the principal characters; and both are composed in an easy kind of mealure, very suitable for fictitious narrative, with no other difference than that the one is written with, and the other without, rhyme.
The fory of Panthea, in Xenophon's Cyropædia, is well known. In the original, it is related with a kind.ofifimplicity so truly pathetic as 10 command fympathy and to invite imita cion : yet in this, as in other cases of a similar nature, the execution has always been found exceedingly difficult. It has been attempted by the ingenious author of The Village Curate: but the imitation, as we had formerly occasion to bemark *, was protracted to a tedious Jength. In the present exhibition of the story, it appears with the addition of much original matter; it is embellished with many incidental descriptions and illustrations, and the sentiments are unfolded at large with energy and spirit. Yet, after all, we question whether the incidents, brought together from the various parts of the Cyrom peedia through which they are dispersed, and told in connection in the limple manner of Xenophon, would not make a ftronger impression on the reader's sensibility. We do not mean, however, to depreciate Lady Burrell's performance. It confirms the opinion which we have already expressed of her talents for easy versification, (lee Rev. New Series, vol. xi, P. 445,) and will perhaps be read with more pleasure than many more elaborate performances. Reserving to our readers the fatisfa&tion of perusing the principal story entire, we shall copy, by way of specimen, a few pleasing lines describing the charac. ter of Tigranes; whole father, with his family, had been made captive by Cyrus :
* See Rev. N. S. vol. vi. p. 283.
• Silent and fad, with folded arms he gaz'd
The tenderest lover in Armenia's realm.'
AŘT. VIII. A Practical Treatije on Peat Moss, considered as in its
natural State fitted for affording Fuel, or as fusceptible of being converted into Mold capable of yielding abundant Crops of useful Produce ; with full Directions for converting it from the State of Peat into that of Mold, and afterwards cultivating it as a Soil. By James Anderson, LL.D. F.R.S. F.A.S. S. Svo. pp. 180. 45. Boards. Chapman. 1794.
E are happy to see Dr. Anderson once more a labourer in the
talents for experimental husbandry, &c. fhould not, under a public establishment, be wholly employed in the public service.
Perfedtion, however, does not belong to human nature. Dr. A. has unfortunately imbibed more than a sufficient quantity of the spirit of modern philosophers, which burries them on to be more anxious about the credit of the discovery than concern
ing its utility: employing themselves in controversy, when they ought to be improving and perfecting each other's ideas.
Dr. A., believing that he has hit on a new idea respecting the propagation of peat-moss, is solicitous to establish it as bis
His essay, he tells us, was written for the Board of Agriculture: but, for reasons given, he judged it better to publish it as a separate work; and in order, it thould feem, to file his DISCOVERY in form, it was previoudly announced to the Royal Society of Edinburgh:
• The first part of the esfay as it now stands, with the postscript, a little enlarged by some additional observations, was read in the Royal Society of Edinburgh, at their meeting on the 6th of January laft; when the author found that, though the members present were Itartled at the novelty of the idea suggested, and inclined for the present to with-hold their afsent to it, yet they were not able to state a fingle fact, or to adduce an argument that tended to invalidate it in the smallest degree. One of the members, respectable for his physical researches, did the author the honour to say the theory was wholly his own.'
We are almost sorry that truth urges us to say that the respectable member was mistaken: as, some time prior to the Oth of January last, we were in poffeffion of the idea : not in the shape of an hypothesis raised in Edinburgh, as the Doctor professes his notion to be, but of an opinion drawn from facts, which arose in the examination of a Highland peat-moss.
Dr. Anderson appears to have had much experience, and to have made accurate observations, on the peat-bogs of Aberdeenshire; and he has formed his theory from them only. Peat-earth, however, is of varied origin: Chat-moss near Man. chester, the peat-grounds about Newbery, and the ordinary mosses of Scotland, are evidently diftinct productions.
Setting, therefore, the Doctor's theory of propagation afide, as not the most valuable part of his bouk, we pass on to his theory of cultivation.
Hé divides his treatise into two parts; considering peat-bog in the distinct capacities of fuel and foil:-Of the former, his experience has led him to speak with great ingenuity and accuracy: respecting the latter, the moft interesting particular arises from a mere thought; an ingenious pian; which, however, remains yet in a state of theory, and is dubiouły practicable. Nevertheless, it is possible that it may prove an excellent thought. Peat-mosles form no small part of the level surface of Scotland : they now lie waste; excepting fo far as they are useful for fuel; and any means of rendering them culturable, at a reasonable expence, would be an acquisition of territory to
Taking it for granted that pressure is the great thing wanted to the productiveness of peat-moss as a foil, Dr. A. offers a plausible and we believe a new idea, respecting the means of communicating pressure to the surface of the tenderest mols. His idea being simple, it is the more easy to form a judgment of its practicability; and we hope that the false delicacy of his friends will not deter others from endeavouring to profit by the proposal : namely, that of giving the required pressure with rollers, drawn over the surface of the moss, by means of moveable wooden foot-paths,' (or rather we should say horsepaths,) provided for the horses to walk upon :' with an ingenious apparatus (but, we think, much too heavy for one Imall horse,' adapted to these paths.
The most insurmountable difficulty appears to be that of turning the apparatus at the ends of the lands, when these do not reach entirely across the moss : a difficulty against which the proposer does not seem to have provided. This, however, by Itudy and perseverance, we doubt not, may be obviated; and the advantage to pofleflors of extensive mofies may become immenfe. By means of such paths, the surface is proposed to be afterward ploughed, &c. and the crop to be carried off.
On the whole, this tract does Dr. Anderson very great credit as a scientific agricultor.
ART. IX. An Account of the different kinds of Sheep found in the Russian
Dominions, and among the Tartar Hords of Alia: By Dr. Pallas,
F. A.S.S. 8vo. pp. 185. 58. Boards. Chapman. 1794.
twelve or fifteen months, in a periodical publication entitled The Bu, published at Edinburgh, under the management of Dr. A.* The eflays were drawn up by a correlpondent of that miscellany, under the signature Arcticus, from the original papers, and with the approbation, of Dr. Pallas; who has travelled through the wilds of Asia in quest of natural knowlege, under the patronage of the Empress of Russia. On these oba fervations, some sensible remarks are made by Areticus, whose ingenuity and public spirit are conspicuous; and to these are added some valuable notes by the editor ; followed by distinct essays (also by Dr. A.) on such interesting topics, or parts of the general subject, as appeared to him most entitled to explana.
* We learn, with regret, that this work is discontinued. Eighteen vols. small 8vo, are completed.