panied, are rational and impressive; and we recommend the volume to a careful perusal, heartily wishing that the benevolent design of the author may be accomplished.

SINGLE SERMON.

Art. 45. The Fall of Eminent Men in Critical Periods, a National Calamity. A Sermon preached at the Gravel Pit Meeting, Hackney, September 21, 1806; on occasion of the recent Death of the Right Hon. Charles James Fox. By Robert Aspland. 8vo. 15. Longman and Co. 1806.

If this discourse was not delivered in one of those splendid and magnificent structures which seem to bid defiance to time, and which shame the puny labours of our days,-if it was not pronounced by a Divine clothed with dignities and distinguished by honours, it pro ceeded from a disinterested breast, and each tittle of it received the sanction of a respectable assembly; in which religious principle braves the dread of singularity, and foregoes the countenance of authority, and from the purity of whose homage no unworthy motive can be supposed to detract. The altar here erected burns not in honour of the powerful Minister, the great public character, and the matchless orator; it offers incense to a rare assemblage of sound principles, bright virtues, and amiable qualities: it is the proper tribute to the man, who, regardless of his own interests, invariably exerted his preeminent powers in the service of his country and of humanity.

The whole discourse is in a highly becoming strain, at once instructive and pious.

CORRESPONDENCE.

A Country Correspondent is very clamorous against what he calls the tricks, deceptions, and under-hand schemes and speculations of book-makers and booksellers,' and he wishes us manfully to expose them: but we must remind him that we do not undertake a wartare against tricks and deceptions in general. If any book-maker or bookseller comes before us, and is convicted of having acted dishonorably by the public, we will as usual write against his name, Hic Niger est, and then let him sin again if he dares. We know, as well as our Correspondent, that new schemes are often stated to be free from all bibliopolal interference, when in fact the prime-mover of them may be marked inter alios, in his place, snug, at the bottom of the title-page.

We are sorry to trespass on the patience of our nautical friend Posco: but circumstances have combined to delay our dispatches, and we cannot get under weigh till we receive our sailing orders. The object in question, however, will not be overlooked.

Mr. L. of Sheffield, seems to have reason in his remonstrance; and so have we in the rejoinder which we could make-His book is sub judice.

THE

MONTHLY REVIEW,

For DECEMBER, 1806.

ART. I. Philosophical Transactions of the Royal Society of London, for the Year 1806. Part I. 4to. 13s. 6d. sewed. Nicol.

CHEMISTRY, ANATOMY, NATURAL HISTORY, &c.

THE Croonian Lecture on the Arrangement and Mechanical Action of the Muscles of Fishes. By Anthony Carlisle, Esq. F.R.S. F.L.S.-The structure and action of the muscles of fish are, in many respects, obviously different from those of other animals; and in presenting to us his observations on this subject, Mr. Carlisle begins by offering some remarks on the purposes which are fulfilled by the several fins. Those which are disposed in pairs appear to be the apparatus by which the animal is enabled to turn its body, or to stop its progress; the single fins prevent the rolling of the body; and the tail seems to be principally useful in impelling it forwards. The effect of the individual fins was ascertained by cutting them off separately in a number of fish, and observing the nature of their motions in the various cases.

Mr. C. next describes the formation of the great muscles, which constitute the bulk of the body; their general appearance is well known, as composed of a number of separate flakes, forming distinct arrangements, which the author calls series; and of which there are four; the dorsal, the vertebral, the abdominal, and the ventral. It is observed that the muscular power of fish is very considerable for a short time, so as to be capable of great velocity, but that it is soon exhausted; and Mr. C. remarks that the mechanism of the muscles is such as is known to produce similar effects in other cases, while an opposite structure is found to prevail in those instances in which velocity is sacrificed to power.

Chemical Experiments on Guaiacum. By Mr. Wm. Brande.In his inquiries respecting this substance, the author first gives an account of its sensible properties, and afterward of its habitudes with different re-agents. Alcohol dissolves very nearly VOL. LI.

Z

the

the whole of it; acids will precipitate it from the solution; and some singular changes take place in the color of the precipitate, when the nitric and oxymuriatic acids are employed, which appear to depend on the different degrees of oxidation that it undergoes in the process. By destructive distillation, guaiacum was found to contain 3 per cent. of lime, but no trace of fixed alkali could be detected. In its general properties, it approaches the most nearly to the class of resinous bodies, but in some circumstances it differs from them,

1. By affording a portion of vegetable extract.

2. By the curious alterations which it undergoes when subjected to the action of bodies, which readily communicate oxygen, such as nitric and oxy-muriatic acids; and the rapidity with which it dissolves in the former.

3. By being converted into a more perfect resin; in which respect guaiacum bears some resemblance to the green resin which constitutes the colouring matter of the leaves of trees, &c.

4. By yielding oxalic acid.

5. By the quantity of charcoal and lime which are obtained from it when subjected to destructive distillation.'

On the Direction of the Radicle and Germen during the Vegetation of Seeds. By Thomas Andrew Knight, Esq. F.R.S.It is commonly known that, when a seed begins to vegetate, the germen always points upwards, while the radicle as invariably tends to the opposite direction; and that, in whatever manner the seed be turned, these parts still preserve their relative situation. In order to ascertain the cause of this phanomenon, Mr. Knight instituted the following experiments. A number of beans were placed in the circumference of a wheel, which was caused to revolve with rapidity in a vertical direction. After some time, they began to vegetate, and the result was that their radicles were all turned outwards, while the germens shot towards the centre. Other beans were then placed in the circumference of a wheel which revolved horizontally; in this case the roots pointed outwards, but were at the same time depressed below the level of the wheel, while the shoots all tended inwards, but were somewhat elevated. The more rapid was the motion of the wheel, the less the parts of the plants deviated from the horizontal position.

From these trials, the author concludes that the direction of the radicles and germens depends on the force of gravity, and he proposes to shew how the same power can produce effects apparently so opposite to each other. To elucidate this difficulty, we have only to attend to the manner in which the growth of these parts is effected. The radicle is extended by

new particles successively added to its point, which will naturally attach themselves to its most depending part: while the germen, on the other hand, is lengthened by the expansion of a structure previously organized, in consequence of the force of the sap contained in its vessels. From this circumstance it follows that, when the point of the germen is bent from its natural position, and the sap is accumulated in the lower side, by its propulsive power it will give the part a tendency to shoot towards the opposite side, and will thus bring it back to the perpendicular direction. Mr. Knight's explanation appears to us simple and ingenious, and his conclusions are very plausible, if not absolutely established.

--

A third Series of Experiments on an artificial Substance, which possesses the principal characteristic Properties of Tannin; with some Remarks on Coal. By Charles Hatchett, Esq. F.R.S.Our readers will perceive with pleasure that Mr. Hatchett has continued his curious and interesting experiments on the artifi cial production of tannin. In his last paper, he gave an account of the action of the sulphuric acid on turpentine, resin, and camphor; and the present is chiefly occupied with the effects of the same re-agent on a number of other vegetable substances, including many of the resins, balsams, mucilages, and gums. The result was that the third variety of the artificial tannin is formed in different proportions from the greatest part of them, accompanied by a quantity of coaly residuum.The paper, which is of considerable length, contains the results of several series of experiments; which, though all tending to the same point, are so far unconnected, that it would be difficult to give any abstracted account of the whole: we shall therefore only select a few of the facts which appear most interesting.

Pure resinous bodies yielded tannin in a large quantity, but little or none was produced from the extracts and gum-resins. It was also procured from linseed oil, wax, and fat: but, if the action of the acid was too long continued, the tannin was converted into a kind of coal.-Some curious experiments were made on roasted vegetable matters. By the operation of roasting, any small quantity of tannin which they might previously have contained was destroyed: but, if a decoction formed from them was treated with nitric acid, tannin was re-produced in a considerable quantity; and it seems probable that, by repeating the process for a sufficient number of times, the whole of them might have been converted into this peculiar substance. It appears likewise that, in the putrefaction of vegetables, the carbon is reduced to a state very similar to that of coal;

and if nitric acid be then applied to it, tannin is also formed.

Mr. Hatchett observes, generally, that acids exercise a considerable solvent power over resinous bodies; the acetous acid dissolves them without altering their composition; while the sulphuric, as we have already stated, in the progress of the solution, converts them first into tannin, and afterward into a kind of coal. The formation of coal appears, therefore, to be the ultimate effect of sulphuric acid on resins; and it exercises an action in some measure similar, on all vegetable substances. This fact leads the author to speculate on the formation of those immense masses of coal which exist in various parts of the world; and, after having noticed the different theories which have been proposed, he concludes that it is most probable that they are derived from vegetable substances which have been mineralized by some unknown process, in which it may be conjectured that the sulphuric acid has borne a principal

share.

We learn with regret that Mr. Hatchett does not intend, at least for the present, to pursue any farther the subject of these experiments. Considering them in their full extent, we do not hesitate to characterize them as the most important series of chemical facts which have, for a long time, been laid before the public, both with respect to the discoveries that are immediately communicated by them, and the information which they bestow on the composition of vegetable bodies in general.

An Account of a small Lobe of the human prostate Gland, which has not before been taken notice of by Anatomists. By Everard Home, Esq. F.R.S.-It had been hitherto supposed that the vasa deferentia passed along the division of the prostate gland, in close contact with the bladder: but we learn from Mr. Home's discovery that a small part of the prostate is interposed between them, and that they pass through a circular aperture, formed by the union of this new lobe with the two which have been previously known to us. Mr. Hame's discovery is not a matter of mere curiosity; since it would appear that the disease of the prostate, when an obstruction is opposed to the flow of the urine, generally commences in this part, and may be exclusively situated in it; and when this is the case, the disease cannot be detected by the usual method of examination, a circumstance which must materially in fluence both our opinion concerning the complaint, and our practice in it. From the statement contained in this paper, there seems no doubt of the existence of this small lobe; and

yet