This curious and elaborate paper, consisting wholly of the detail of particular experiments and observations, is not susceptible of either abridgment or extract. Observations of the Diurnal Variation of the Magnetic Needle at Fort Marlborough in the Island of Sumatra. By John Macdonald, Esq.-Consisting of Tables. Particulars of the Discovery of some very singular Balls of Stone found in the Works of the Huddersfield Canal. jamin Outram, Engineer. By Mr. Ben In perforating a hill by a subterraneous tunnel for this canal, at the depth of about 90 yards from the surface, the workmen met with a fault or break of the strata through which they were cutting, in which they found a rib of limestone, and a number of balls of limestone scattered promiscuously, of various sizes, from one ounce to upwards of 100 lbs. weight. These are not pure limestone, but mixed with a kind of pyrites, and are all somewhat flattened on two opposite sides. No limestone has been discovered on the surface of the country, within 20 miles of this place. Account of the Earthquake felt in various Parts of England, Nov. 18, 1795; with some Observations thereon. By Edward Whitaker Gray, M. D. F. R.S. Happily for this country, the circumstances attending that phænomenon of nature so much dreaded in many parts of the world, under the name of earthquake, are here so little striking or alarming, that very close inquiry is necessary to trace the minute footsteps of such an event. In the same proportion, too, we should conceive that its importance as a subject for philosophical observation is lessened; and indeed few narrations appear to us more tedious and uninteresting, than the very diffuse accounts, with which the public have so often been favoured, of earthquakes in Great Britain. We are not able to make an exception to this remark, with respect to the paper before us; which, indeed, the writer concludes with becoming diffidence as to his observations on the mixed causes of this phænomenon, and with a hope that our island will continue to contribute but a small share of those materials which are still wanting to form a complete theory of earthquakes.' A Description of the Anatomy of the Sea Otter, from a Dissection made Nov. 15, 1795. By Everard Home, Esq. F.R.S. and Mr. Archibald Menzies. This paper consists entirely of particular description, and is lustrated by plates. REV. APRIL, 1797. Ff Observations Observations on some ancient metallic Arms and Utensils; with Experiments to determine their Composition. By George Pearson, M. D. F.R.S. We have seldom seen greater accuracy displayed than in the paper before us; in which every mode suggested by analysis and synthesis, in the determination of the proposed questions, has been employed with surprising minuteness. Whether the subject deserved such a degree of attention, we shall leave to the decision of the reader; the really important part of it appears to us to be the investigation of the nature of those metallic mixtures which, before the use of iron was common, were employed for purposes for which hardness or sharpness was requisite. From the chemical analysis of some implements of this kind found in the bed of the river Witham in Lincolnshire, and given to Dr. Pearson for the purpose by Sir Joseph Banks, it is ascertained, almost with certainty, that the metallic mixture of which they were made consisted chiefly of copper, allayed with a portion of tin, and of no other metal. This discovery leads Dr. P. to the refutation of the common hypothesis, that the antients possessed an art of tempering copper to a hardness approaching that of iron, which is now lost. We have here to observe that a remark, with respect to the mistake into which Dr. Priestley had fallen on this head, may be found in the Monthly Review for December 1794.-The observations on some rusty steel instruments, discovered with the rest, seem to be of little consequence. Observations on the Changes which Blood undergoes when extravasated into the Urinary Bladder, and retained for some Time in that Viscus, mixed with the Urine. By Everard Home, Esq. In consequence of a case in which blood, discharged into the urinary bladder, coagulated there, and prevented the natural evacuation of the urine for about 30 days, Mr. H. made several experiments on the mixture of blood with urine out of the body, compared with its mixture with water. The general result was, that blood is capable of uniting with a quantity of urine equal to itself, so as to form a firm coagulum; that the red globules do not dissolve in a coagulum so formed; that an admixture of urine prevents the blood from becoming putrid; and that the coagulating lymph breaks down into parts almost ' resembling a soft powder.' On the Fructification of the submersed Alga. By Mr. Corrêa de Serra, F. R.S. The purpose of this ingenious paper is to prove that the grains found in these plants are real seeds, and that the mu 8 cous cous substance surrounding them is a true fecundating pollen, adapted for existing under water without injury to its properties. The conclusion of the writer's reasoning is, that the vesicles of all these subaqueous plants, whatever be their shape, if containing grains and mucus, are to be considered as hermaphrodite flowers. The MATHEMATICAL and ASTRONOMICAL Papers are reserved for a future Article. ART. IX. A Treatise on the Improvement of Canal Navigation; exhibiting the numerous Advantages to be derived from small Canals, and Boats of two to five Feet wide, containing from two to five Tons Burthen. With a Description of the Machinery for facilitating Conveyance by Water, through the most mountainous Countries, independent of Locks and Aqueducts: including Observ ations on the great Importance of Water Communications; with Thoughts on, and Designs for, Aqueducts and Bridges of Iron and Wood. Illustrated with seventeen Plates. By R. Fulton, Civil Engineer. 4to. pp. 144. 18s. Boards. Taylor. 1796. WHOEVER thinks deeply on any subject, and candidly com municates to the world the result of his investigations, confers an obligation on the public which ought to entitle his endeavours to a kind reception, even if he should not have been able fully to accomplish the object of his wishes; for ideas once started may suggest hints to those who would not otherwise have adverted to the subject, and may thus be productive of benefits that were not originally conceived. The present work owes its rise to a circumstance of this sort, which the author, in his introduction, mentions in the fol lowing terms: On perusing a paper descriptive of a canal projected by Earl Stanhope in 1793, where many difficulties seem to arise, my thoughts were first awakened on this subject.' He then proceeds to state the gradual progress of his ideas. The volume before us is professedly written with a view, not absolutely of deciding on the subjects here treated, but of directing the attention of inquirers to some points, which the author considers as of great importance towards rendering internal navigations more useful than they have hitherto been; and we are of opinion that it suggests several hints which deserve to be farther elucidated. Mr. Fulton begins with a chapter on the origin and progressive improvement of canals; followed by another, on the importance of Ff 2 canal Ai. canal navigations, and e benefits arising to society by easy commu nications; which may be considered as merely introductory, and matter of general observation. In the IIId chapter he proceeds to develope his plan, and to recommend the adoption of small canals in preference to those of larger dimensions. The former, he endeavours to shew, would not only diminish the expence, but also, in many cases, expedite the carriage of goods by lighter and swifter boats. The same idea is pursued in the IVth chapter. After these preliminary discussions, the author gives, in the Vth chapter, a particular description of the boats which he most approves, and of their application to various situations. Without the aid of figures, we cannot impart to the reader precise ideas on this head. It falls more conveniently within our province merely to observe, that Mr. F. recommends the use of boats not exceeding four or five tons burthen; and that, instead of locks, he prefers an inclined plane for elevating and lowering the boats from one level to another, by means of machinery of his own contrivance; in the construction of which he discovers no small share of ingenuity, although we think that we perceive strong symptoms of his being better acquainted with the theory than with the practice of mechanics. He does not propose that the boats should be put into a cradle for the purpose of being transferred from one reach to another, but that they should move along the inclined plane on small wheels fixed to the boat for that purpose, which should be so placed as to occasion no sensible retardment to the boat while floating in the canal. The succeeding chapters, to the XVth, consist of explanations of the plates, calculations, and illustrations, which admit not of abridgment: but all tending to manifest the superior advantages of the mode of navigation proposed, when compared with that which is in common use, by means of locks. The following extract will serve to give the reader some idea of this part of the work, viz. A COMPARATIVE VIEW of the EXPENCE of raising 100 FEET, by Locks or INCLINED PLANES, the usual Expence of Locks for twenty-five ton Boats, being 70l. per Foot, and for forty-ton Boats 100l. which, in the first Case, would cost 7000l. and in the second 10,000/ In this I shall consider the average of situations and circumstances, as to the form of the ground, carriage of materials, &c. the plane on an angle of 20 degrees. Removing Removing 4000 cube yards, in forming the slope of the hill, at 5 d. per yard, To forming the ends of the canal, top and bottom, 536 cube yards rubble walling, at 55. per yard, 268 yards squared ashlar coping, 18 inches thick, 3 feet long, at 15s. the running yard, 536 yards cast-iron rails, 100 cwt. per yard, 15 s. per cwt. Bedding the rails in the coping, lead and pins, 2 s. per yard, 26 cast-iron binders to unite the planes, 200 cwt. each, at 155. per cwt. 2 horizontal wheels, 8 feet diameter, 6 inches on the face, 800 feet chain, 2 s. per foot, 34 yards tub pit, 11 feet diameter, 41. 10s. per yard, 110 yards sough, at 12 s. per yard, 700 feet of chain to the tub, weight, and balance, 4s. per foot, бо 140 One wrought-iron tub, Drum wheel, 8 feet long, 4 diameter, spur-gear, &c. 60 rollers to bear the chains off the plane, 5 s. each, Contingencies, 10 per cent. Locks for 25-ton boats, 100 feet rise Saving, Locks for 40-ton boats, 100 feet rise, Saving, 100 150 10 15 200 In case of a trade totally descending, the loaded boats raising those that are empty, the tub, pit, drum wheel, and all that part of the machine for creating power, may be saved, amounting to 5991., the contingent expences being reduced in proportion; in which case a double inclined plane, to the height of 100 feet, would cost 1635 l. 161. This, compared with the expence of locks for 25-ton boats, will be a saving of 53641. 4s. and on locks for 40-ton boats 83641. 4s.' The author endeavours to prove that the saving, in other respects, will be nearly in the same ratio. Ff3 In |