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fide MIDWIFERY, 39. Amidst all these treatises we are surprised not to find PHYSIOLOGY. The word indeed occurs, but instead of a treatise on the subject, or even an accurate explanation of the term, we have only See Pbypology.' Such strange inaccuracy we remember not to have before met with. The neglect of this very important branch of medicine is the more blameable, fince it is universally allowed to be one of the chief corner-stones of the healing art, and the only foundation on which a true and rational theory can be erected.

Medicine, however, is not the only science which admits of a number of different branches arranged in different places. The treatise on Optics, which occupies 160 pages, does not contain : the whole of that science; but we have diftinct and separated treatises on Catoptrics, Dioptrics, Chromatics, &c. inserted in their respective places in the alphaber. How can the compilers call this method concise ?

In philosophical subjects of all kinds, the same method is pursued, but with some alterations. Since all natural philosophy is founded on mathematical principles, we thould have thought that these principles would have been attended to, or at least such fundamental parts of them as are absolutely necessary for the explanation of the more common phenomena in nature. Conic sections, for instance, are dispatched in three pages; we expected to find the various properties of the different curves enumerated at least, if even the demonftrations of them had been with-held. The whole doctrine of Auxions, too, is comprised in four pages. These two branches of the mathematics are abstruse, and the many useful theorems they contain are not easily recollected by people not continually employed about them ; consequently, a recital only of the various propofitions concerning the curves and fluxions would have been highly proper, especially, as we have before observed, that works of this kind are calculated rather to refresh and allift the memory, than to instruct.

Mechanics is a science of infinite use in life; its principles therefore cannot be too fully explained and elucidated; but the compilers of this performance have rio otherwise treated this subject than Ferguson had done before them, the whole of their treatise upon it being copied from that ingenious popular philosopher, who, disregarding fundamental truths, exhibiis but the externals of science. Had this been the only defect, it might have been excusable; but blunders, owing either to inadvertency or any other cause, are unpardonable. An inftance of this we meet with under the word pendulum :. 'The . times of vibration in different pendulums are as the square roots of the times of vibracions :'-instead of The times are as the : square roots of their lengths.'

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Hydrostatics and Hydraulics have been equally obliged to Ferguron's lectures,--the whole of his book, tables and all, being transferred into these articles.

The doctrine of Pneumatics is reduced to the small space of fix · pages; the whole of which conlists of a few unconnected and

unimportant 'entertaining' experiments on the air-pump. This instrument, with all its improvements, would have been a very proper article in a dictionary, but we have no account of its construction, or any history of the many improvements made upon it by almoft every philosopher of nore, from its first invention to the present time. Under this head we expected to find something laid about the barometer, but we were disappointed, and referred to the article Barometer. Turning to Baromeler, we find indeed an accurate description of it, occupying no less than 12 pages, with a long detail about the Torricellian controversy, and other matters that might have been as well falled over in filence : while the most uselul part of the subject is unnoticed ; namely, the construction of weather glasses upon true principles. Thermometers, indeed, are largely created, and full directions are given about filling, dividing, and framing them.

The scientific articles in this performance, which reem best executed, are those in natural history, especially in the animal and vegetable kingdoms; for beside complete treatises on Zoology, Botany, and Mineralogy', giving an account of the various systems of different authors, and describing the subjects of each kingdom, with their generic differences, we find also treatises on cach class of the inhabitants of the animal kingdom, as Orni. thology, Entomology, Conchology, &c, all which articles are translations from the Amænitates Academicce; or, at least, very judicious abridgnients of them. Botany and Mineralogy have been equally attended to; and beside these several diftinct treatises, each genus is particularly described in its proper place in the alphabet. Though the compilers follow Linnæus in Zoology and Botany, they have rejected his system of Mineralogy, and adopted that of Swab, commonly known by the name of Cronsted's fyftem. Various have been the opinions of the learned about these two fyftems; each of them are undoubtedly excellent, and each of them have also their imperfections. The system of Linnæus iş founded entirely on the outward appearance of the objects, while that of Swab depends on the principles of chemistry, and the component parts of the bodies. The advocates of the latter prefer it, because it is better adapted, in their opinion, to Metal. Jurgy; but surely the former is not deficient on this account. According to Linnæus's system, we are taught by the external form and appearance to judge of the internal Itructure and component parts of minerals, a method much readier and iriore easily practised than Swab's, though perhaps not so certain.

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Although we think the natural history not ill executed in this compilement, yet we meet with several things that are triling, nay some that are even ridiculous; for example, a Genealogical table of the different races of dogs. Under the article Cock, we have a long account of cock-fighting, deducing the antiquity of the art from Greece. Bull-baiting is also traced from the reign of our King John: but not a word of bear-baiting, or chuck. farthing. Chemifry has, within these few years, received quite a new face. The many improvements that the present age has made in so useful a science, are of the greatest importance; but we meet with very few of them in this part of the work, which we are nevertheless told contains all the latest discoveries and improvements.' ! Apronomy. This treatise fills rather more than 100 pages. Moft of it is copied from Ferguson, or rather the whole of Fer. guson's Aftronomy is here inserted, with some little matters from other authors. We have a great quantity of metaphysical diso quisition about gravity and attraction, cause and effect, &c. Every objection against the Newtonian 'philosophy is here set forth in ostentatious parade; but to what purpose we know not, except it be merely for the sake of swelling out an article. A system founded on the unalterable laws of nature, and supported by the undeniable evidence of mathematical demonstration, cannot be overturned by the quibbling of school jargon or the false notions of atheistical scribblers. The compilers have followed some French writers, who have called the Newtonian system the Newtonian hypothesis of Gravity or Attraction. They have also made a filly and futile objection to the equality of ultimate ratios. . • While we were pursuing this examination of what the Au. thors of the Encyclopædia had advanced concerning the Newtonian philosophy, we turned to the word Gravity, which we are informed is an incorporeal or spiritual substance that never can be perceived by any other way than by its effects.' Could any one suppose the age we live in, and the country where philosophy has been so much cultivated and improved, to have produced a book containing such a passage? an incorporeal substance ! a body and no body! For more particulars concerning gravity we are referred among others to the words Plenum, Vacuum; the former of which is barely noticed, and the latter article, confisting of three pages, is full of old hypothetical matier. Under Attraction indeed we find something like a definition; namely, the cause by which bodies tend towards each other;' though it is by no means a satisfactory one.

The mathematical articles are in general extremely defe&tive; especially such as are of most univerlal and effential utility. Al

gebra,

gebra, which is so extensively useful in every part of pradical mathematics, and is the foundation of arithmetic, might bave been much enlarged, not only in the treatise under the word Al. gebra, but in several other places in the alphabet. This circumItance, however, might be of little consequence, compared to some capital errors in the definitions themselves. For example,

Series, in mathematics, is a number of terms, whether of numbers or quantities, increasing or decreasing in a given proportion. How will the following agree with this definition : mart -ptr, &c. ad infinitum ? The terms of this series neither increase nor decrease, yet it is univerially called a series, and has been the cause of much speculation among the mathema:icians of the present age. We expected to have met with something concerning the summation of series, or their properties explained; but nothing on the subject of series is to be met with in any part of this voluminous work, except the imperfect definition above. The writers on the serics might have been mentioned ; the labours of Bernoulli, of Newton, and others, in order to discover the properties of infinite series, deserve to be recorded; the inventions and contrivances of these great men, and of Waring, and others among the moderns, in order to determine the sums of series, are too ingenious and useful to have been passed over in silence.

The Arts we expected would have been particularly taken notice of; but we were disappointed. Agriculture and architecture however are more enlarged on than others, but they are at the beginning of the alphabet. 'The necessary arts of Dying, Tan. ning, and Weaving, are flightly noticed, although they are very material articles in a commercial country, especially our own, where they form a considerable branch of our manufaćtories, The destructive art of War, notwithstanding ample articles under the words Artillery, Fortification, Gunnery, &c. is extended through no fewer than 133 pages. We find also a large treatise on Naval Tallics.

Among the mechanical arts, none have received greater improvement, of late years, than clock and watch-making. When navigation became a new science, by the invention of the compale, accurate time-keepers were much wanted, for finding the longitude at sea. In consequence of which, a variety of improveinents were made on the very imperfect machines then in use, and a great number of inventions rendered clock making almost a new art. The applying of pendulums and balance springs to the movements of clocks and watches, was a great and important contrivance; and the various methods made use of to cause a uniformity of motion are to be ranked among the most useful inventions of the present age. In examining how the compilers had taken notice of these circumstances, we find, that, in so great a field, the most material parts are in a cursory manner related'; but the history is so scattered under the various words Longitude, Clock, Watch, Pendulum, Time-keeper, Harrisori, Navigation, &c. that it is no easy matter to collect all that is laid upon the subject. The application of pendulums to clocks is here ascribed to Galileo; yet it is certain, that we have accounts of clocks similar to ours, being made in the time of Edward the Third, who granted, in 1368, a licence to three artists to come from Holland, and practice their occupation in England; and of clocks made of brass in the reign of Charlemagne, to whom one was presented by Aaron King of Perfia, in the year 807. As to watches, our compilers affirm that the invention of of pocket watches belongs to the present age.' We are surprised to see such an assertion when so many proofs of their greater antiquity are upon record. Mr. Barrington gives a full and satisfactory account of a pocket watch, belonging to Robert Bruce, who began his reign in 1305, of wbich we gave an account in our Review for April 1780. We have accounts of repeating pocker watches as early as the time of Charles the Fifth, who had one stolen out of his pocket, and the thief was detected by its striking the hour. In Shakespear's Twelfth Night, Malvolio says, “I frown the while, and perchance wind up my watih, or play with fome rich jewel,' Guy Fawkes had one found upon him, with which he and Percy used to try the times of the burning of touchwood, for setting fire to the train of powder..

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We find in this work, however, a very good account, drawn from the Supplement to the first edition of the Biographia Britannica, of Mr. Harrison's labours and contrivances; and the great degree of perfection to which these instruments have been brought by him, and by Arnold, copied, literally, from our Review, Vol. LXIII. p. 198–207. The various methods in which time-keepers are used for finding the longitude of a ship at sea are sufficiently described ; but the great improvement which navigation has received by the methods of finding the longitude from the distances of the moon from the sun and fixed ftars, is not any where to be met with.

We have several instances of extraordinary definitions occur. ring in this performance :- perhaps none is more curious than the following: 'Artist, a person pofseffing an habitual power of becoming the cause of some effect. Query, are such things below criticism, or above it?

Hanging, we did not expect to find in a Dictionary of Arts and Sciences, and are yet at a loss to determine whether it is an art or science. In the article Drowning we meet with the methods made use of for the recovery of people apparently drowned, hanged, or suffocated; which are judicious, and may be serviceable.

Christianity,

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