moving a few Balls, a great Varies of Operations in Arithmetic may be performed. By W. FREND, Esq. London. THIS volume is designed for mothers, who are very much obliged to Mr. Frend for this present to them, by which they may amuse, and at the same time instruct their children. The basis of it is an arithmetical toy, similar to the Chinese board for numbering; and from the making of a mark to signify one, and setting the first lesson, one and one makes two, the author proceeds, by a variety of simple instances and amusing games, to teach the four first rules of arithmetic. We can assure mothers that, if they persevere in the plan pointed out in this work, accustoming the child to read every day the instances in this book, work them on the toy and with counters, and write out completely the tables at the end, they will have prepared their children very completely for future instruction at school. We are sorry to find that Mr. Frend should have employed his pen so much for the benefit of others, and so little for his own, as the greater part of the first edition was destroyed by fire. The announcing in this edition his intended first book in arithmetic for learners, will be received with pleasure by all teachers, as a work of this kind has been very much wanted. CHAPTER XXII. GENERAL SCIENCE, THE only original publications belonging to this chapter are the annual volume of the Philosophical Transactions, and a fasciculus of the Edinburgh Transactions. The new volume of Dr. Rees's Cyclopedia will not be found to be inferior in merit to the preceding parts of that highly respectable work. ART. I.-Philosophical Transactions of the Royal Society of London for the Year 1805. 4to. pp. 350. IT would be superfluous to give any opinion of the collective merit of the vo 1. The Croonian Lecture on Muscular Motion. By ANTHONY CARLISLE, Esq. F. R. S. This memoir consists, for the most part, of general observations on the composition and properties of muscular substance, and its connection with the vascular respiratory and nervous systems: the drift of the author is not very obvious, nor are his desultory remarks and experiments capable of analysis. 2. Experiments for ascertaining how far Telescopes will enable us to determine tery small Angles, and to distinguish the real from the spurious Diameters of Celestial and Terrestrial Objects, with an Application of the Result of these Experiments to a Series of Obserrations on the Nature and Magnitude of Mr. Harding's lately discovered Star. By W. HERSCHEL, LĻ. D. F. R. S. &c. Our knowledge of the heavens, from the increased number and care of observers, increases daily, and our own country asserts its claim to a share in the triumphs to be obtained by better arts than those of the sword. The writer of this paper is distinguished by having given his name to a new planet: Olbers and Piazzi have enriched the heavens by their discoveries of two wandering bodies, which also bear their names, and another lume before us, as we are about to notice each paper separately. wandering body has lately been discovered, which we trust, will bear, as it ought, the name of Harding. A foolish then mythology, and ridiculously enough affectation attempts to preserve the hea will impose on this small wandering orb the name of Juno, the queen of heaven, the wife and sister of Jupiter : but we shall not readily consent that the discoand whether Harding is to be called a verer shall be thus deprived of his rights, planet or an asteroid, whether he is to take his seat in the house of lords or the house of commons of heavens, in one of them he shall be placed, and the name of Harding shall grace the celestial catalogue. The observations made upon Harding in this paper are very curious, and will be eagerly perused by practical astronomers, The writer received an account of this new celestial object on the 24th of September. Harding was then in the constellation of the fishes, nearly in the line between 29 and 33; and, compared with the very small stars near to it on the 29th, was estimated to be similar to a star of the ninth magnitude, and it is concluded that Harding is less than Olbers. Its motion was retrograde. On the 5th October it had approached near to the fishes, and on the 8th every opportunity was given, from the clearness of the night and situation of the object to make an excellent observation. The writer concludes that Piazzi, Olbers, and Harding, are bodies of the same kind. The appearance of the new object has been productive of several very valuable experiments, which do great credit to the writer, and promise to bring posterity to a better arrangement of the stars with respect to their apparent magnitude. These experiments were made with heads of pins, globules of sealing-wax, globules of silver, of pitch, bees'-wax, and brimstone; these objects were placed at various distances, sometimes illuminated and sometimes not. Their magnitudes were also various; of the pins' heads ,1375,0803 ,0821,0602,0425 of an inch; of others much smaller of sealing-wax, from ,0406 to,00763: of silver, from ,03956 to ,00556, and there was one of brimstope as low as ,0015625. The experiments began with the pins' heads, placed in a regular order on a post, 2407, 85 inches from the centre of the object of a ten-foot reflecting telescope, when the smallest of them appeared with an eyeglass of four inches to be a round body, and shewed, therefore, the necessity of nsing globules more minute. The effect of different powers upon these different globules is explained with great accuracy, but we must copy the whole paper to give the reader a true idea of the value of its contents. From experiments like these we shall come to a better discrimination between the real and spurious diameters of celestial objects, and probably they will lead to judicious conjectures on the belts of Jupiter, and the spots in the sun. If we can reason only from what we know, it seems to be not an unsuitable method in our progress to knowledge, to place objects on earth in various points of view, till we make them resemble as nearly as possible those in the heavens, and the illuminating of these objects on earth, as performed by the writer of this paper, will assist very much the practical astronomer in his researches. 3. An Essay on the Cohesion of Fluids, by T. YOUNG, F. R. S. &c. The cohesion of fluids is a subject of a very difficult nature, and little has been done of late years to explain it satisfactorily. This paper is a specimen of what we may expect from the writer in a larger work, which he is preparing for the public. He considers the form, which the surface of a fluid takes, when at rest, and ANN, REV. VOL. IV. this surface is examined on mathematical principles, from the nature of tension, and its convex or concave form is thus very ingeniously explained. It leads to complex expressions and fluxional equations, on which our limits will not permit us here to dilate. The heights to which fluids rise, the apparent attractions and repulsions of two floating bodies, the physical foundation of the law of superficial cohesion, the cohesive attraction of solids and fluids, form subjects of enquiry. On all of these the writer could, in so short a paper, only lay his ideas before the Royal Society in the shortest possible compass, and of course a considerable degree of obscurity envelopes the whole, This we hope will be dispelled in the approaching publication, which we recommend to be delayed till the president and council are perfectly masters of its contents. Two kinds of say are found in trees, namely, the common aqueous sap and the peculiar juice, suc propre, or true sap, This latter, according to some experiments of Mr. Knight, detailed in the Transactions for 1801, appears to be elaborated from the common sap, by means of the leaves, and the object of the present paper is to show that this fluid in an inspissated state, or some concrete matter deposited by it, exists during the winter in the alburnum, and that from this fluid or substance dissolved in the ascending aqueous sap, is derived the matter which enters into the composition of the new leaves in the spring, and thus furnishes those organs which were not wanted during winter, but which are essential to the futher progress of vegetation.' If this theory be true, it will follow that timber, felled in winter before the ascent of the sap, will be more compact, of greater specific gravity, and will afford a larger quantity of extractive matter, than timber similar in every other circumstance, except in having been felled in the summer: it may also be expected that the common aqueous sap, as it ascends towards the extremities of the tree, should be sweeter and of greater specific gravity than when it is discharged from the roots into the trunk of the tree. In pursuance of this train of reasoning, Mr. Knight made in, 3 K cisions in various sycamore-trees early in the spring, and found that in all of them the sap extracted from the bottom of the trunk, on a level with the ground, was = 1.004, whereas that which flowed from an incision in the same tree, at the height of seven feet, was = 1.008; and in one instance at twelve feet from the ground, he obtained a very sweet fluid of the specific gravity of 1.012. This point being ascertained, Mr. Knight imagined that if the increased specific gravity of the sap was owing to the solution of matter previously existing in the alburnum, some diminution in the gravity of the sap would take place when it had continued to flow several days from the same incision, the soluble matter of the alburnum being in this case nearly exhausted. This was verified by experiment; an incision being made in a sycamore-tree close to the ground, gave a liquor at first of the specifie gravity of 1.004, but after a few days running it had diminished to 1.002. For ascertaining the differences in the specific gravity of the alburnum itself, poles were selected from an oak coppice, of equal age, and as similar as possible in other respects; of these some were cut on the last day of December, and the rest on the 15th of May following. The summer-felled wood was, before drying, the heaviest, but when both had been exposed for an equal time to the same temperature, and were become perfectly dry, the specific gravity of the winter-felled wood was ascertained to be = 0.679, while that of the summer-felled wood was only 0.609, after each had been immersed in water for five minutes. In the same manner equal weights of the two woods, being digested for the same time in boiling water, it was found that the colour of the infusion was deeper, and its specific gravity greater, in that where winter-felled wood had been employed than in the former. In the remainder of this interesting paper Mr. Knight proceeds to show that the expansion and growth of leaves is owing to the passage of sap in them, and that these, in return, elaborate the watery sap into the proper sap of the tree, which then passes by appropriate vessels out of the leaf into the alburnum hence it is distributed during the summer to the various buds and leaves, but in the autumn is accumulated in the alburnum, for the supply of the first leaves in the ensuing spring. : From this it appears that Mr. Knight, in opposition to most vegetable physiolo gists, believes in the proper circulation of the sap. 5. On the Action of Platina and Mercury upon each other; by RICHARD CHE NEVIX, Esq. F. R. S. M. R. I. A. &c. It cannot be unknown to any of our chemical readers, that a paper by Mr. Chenevix was published two years ago in the Philosophical Transactions, the object of which was to shew that mercury and platina were capable of entering into very intimate union with each other, and that the substance called palladium was the result of this combination. Several of the continental chemists have complained that Mr. Chenevix's experiments have totally failed in their hands, on which account they are induced to question the accuracy of this able chemist. The first part of this memoir is devoted to answering these objections; by showing, that in some instances his opponents have materially varied from his directions in making their experiments, and that in other cases they have not been repeated sufficiently often; for Mr. C. in his original paper, expressly says, that his failures were much more frequent than the instances in which he was successful; and in that now before us he says: "The course of experiments which I had made, as well before as after reading my paper to the society, took me up more than two months, and employed me from twelve to sixteen hours almost every day. I had frequently seven or eight operations in the forge to perform daily, and I do not exaggerate the number of attempts I made during this time, as well in the dry as in the humid way, in stating them to have been one thousand. tions. I persevered, because even in my Amongst these I had four successful opera failures I saw sufficient to convince me that'l should quit the road to truth if I desisted. After all my labour and fatigue I cannot say that I had come nearer to my object, of ohtaining more certainty in my processes. Their success was still a hazard on the dice, against which there were many chances; but till had no solid right to deny the existence of others had thrown as often as I had done, they such a combination." After some reasoning from analogy, to show that a successful experiment, unexceptionably conducted, is not to be set aside by any number of failures, Mr. C. quits the subject of palladium, and gives a new example of the fixation of mercury by platina, the result of which, however, was an alloy very different from palladium. When muriat of platina, and green sulphat of iron, are mixed together, no precipitation or any other sensible change ensues, but if to this compound solution, the nitrat of silver or of mercury is added, a very copious precipitate of platina and the other metal in the reguline state falls down; none of the salts of any other metal produce the same effect. It is therefore fair to conclude that when a solution of platina is precipitated in a metallic state, by a solution of green sulphat of iron, either silver or mercury is present.' Now if a solution of nitrat of mercury, at a minimum of oxydation, is added to muriat of platina, a mercurial muriat of platina will be precipitated. This being washed and exposed to a sufficient heat with borax, is reduced to a metallic button, which, when afterwards dissolved in nitromuriatic acid, and mixed with green sulphat of iron, affords a precipitate. Again, if a current of sulphuretted hydrogen gas be sent through a mixed solution of platina and mercury, and the precipitate which ensues be collected, the alloy may be reduced by heat, and by means of borax may be melted into a button, which will not contain any sulphur. If this is then dissolved in nitro-muriatic acid, and green sulphat of iron poured into the solution, a precipitate will take place. Hence Mr. Chenevix concludes that the metal in both these instances is an alloy of platina and mercury, and consequently that the latter metal may be thus fixed, that is, enabled to bear a high heat without volatilization, 6. An Investigation of all the Changes of the zariable star in Sobieski's Shield, from five Years Observations, exhibiting its proportional illuminated Parts, and its Irregularities of Rotation, with Conjectures respecting unenlightened heavenly Bodies. By E. PIGOTS, Esq. Some account of this star has been already published in the Transactions, and the writer gives us in this paper his obser-vations from 1796 to 1801, dating the first part from Bath in 1802, and the latter part from Fontainebleau in 1803. In the former part are given various tables of the days of greatest and least brightness, middle of greatest and least brightness, rotation calculated from observations of greatest and least brightness; from which it is calculated, that the star has a rotation in sixty-two days, that the mean duration of maximum brightness is nine days and a half, and of its minimum brightness nine days. From these observations the writer concludes that the bodies of the stars are dark and solid, their real rotations on the axis regular, that the surrounding medium generates and absorbs its luminous particles in the manner conjectured by Herschel with respect to the solar atmosphere, and in the star of Sobieski these luminous particles are very sparingly dif fused, that they are in patches upon the star, and the relative situation of these patches may be conjectured from observations on the increase and decrease in the star's brightness. On the last subject the writer has followed a similar plan to that which Herschel used in his observations on the planet Harding, and which cannot be too much recommended. He placed small white spots on a dark sphere, by whose revolution he attempted to describe the changes as perceived in the star. The scheme seemed to answer very well, but we must leave to many more years observations the verification of the conjectures formed either by Herschel or this writer. We could not but smile, however, at the writer's admiration of the happiness enjoyed by the inhabitants of the planet on which we live, above that of the persons who derive their light from the star in Sobieski. How far more enviable seems our situation! Lest we might pride ourselves too much upon it, he corrects himself on our happiness, for who knows but our sun may hereafter be as scantily provided with luminous particles as the star in Sobieski? But such conjectural flights cannot too soon be dropped, and we commend phy: the former we recommend to every the observations more than the philoso wish to be reserved for a distant genepractical astronomer, the latter we would ration, or a period of greater certainty. 7. An Account of some analytical Experiments on a Mineral Production from Devonshire, consisting principally of Alumine and Water. By HUMPHRY DAVY, Esq. F. R. S. Professor of Chemistry in the Royal Institution. This mineral was found by Dr. Wavel near Barnstaple, filling the cavities and veins of a soft argillaceous schistus. It occurs generally in small hemispherical groups of filamentous crystals, radiating from a common centre, or forming small veins. Its colour is greyish or greenish |