an attempt to give a clear and concise account of the prefent state of anatomical knowledge, will perhaps not be deemed improper or unnecessary.'

With the alterations which have been made in the text, and the remarks contained in the fubjoined notes, this work muft be confidered as an improvement on the original. But notwithstanding the pains which feem to have been taken to render it compleat, fome little errors may ftill be found uncorrected, and fome flight defects unfupplied.-We fhall inftance a few of them.

Under the article of Cartilages-it is afferted that they as well as the bones are infenfible.'-To explain and qualify this affertion, the following note is given by the Editor.

In the course of this volume mention is often made of the fenfi-' bility or infenfibility of different parts, and it will perhaps not be amifs to give the outlines of a fyftem, which cannot but be interefting to all anatomical readers.-Baron Haller was the first who publicly afferted, that living animals, whofe cartilages, ligaments, capfale of the joints, tendons or periosteum were cut, burnt, or torn, fhewed no figns of uneafinefs, and that the wounds of all these parts were cured without any bad fymptoms.-In his publications on this fubject, he allows feeling to the teeth, but not to the bones, because they are destitute of nerves.-He ventures to deny fenfibility to the marrow, not from any experiments of his own on living animals, but because it is a fatty fubftance without nerves.-He tells us, that when the dura mater was torn or burnt with oil of vitriol, the animal feemed infenfible of the injury-that with the pia mater it was the fame, but that the moment the brain itself was wounded, the body of the animal was exceedingly convulfed-he makes the fame conclufions from fimilar experiments on the peritoneum, pleura, and pericardium, and of the mediaftinum from its analogy to them as a membrane, and defcribes the cornea as infenfible, because its nerves cannot be demonftrated, and it is often pierced with a needle without pain. From a variety of interelling experiments, which he has fully related, he concludes, that all thefe parts are perfectly infenfible, that they have been unjustly accufed by phyficians as the feat of many painful difeafes, and that their infenfibility argues their being deftitute of nerves-he will not allow the pain and inflammation of the arm, which fometimes are the confequences, of bleeding, to proceed from the tendon or aponeurofis in that part, but attributes them to an injury done to the median nerve or to fome branch of the mufculo-cutaneous nerve.-He afferts, that the phrenitis has not its feat in the dura mater, or the pleurify in the pleura-That in the gout, the skin and subcutaneous nerves, and not the ligaments or capfulæ of the joints, are the feat of pain.-Thefe are the most important points of the Baron's fyftem, but his opinions have been much controverted, and the late Dr. Whytt, in particular, favoured the public with many fenfible arguments in refutation of this doctrine, which, however, if not thoroughly received in its full extent, is now in a great measure admitted. The ingenious Dr. Hunter, who ap

pears

pears to have remarked the infenfibility of fome of thefe parts before. the Baron's publication of his fyftem, fufpects that the Baron has gone too far in afferting, that they have abfolutely no fenfe of feeling-He thinks that experiments on brutes are not fufficient to afcertain the more exquifite fenfations of the human body; and is of opinion that the Baron has been led into an error in furgery, in fuppofing that the effects of wounds of the tendons, ligaments, &c. are so very fimple as to heal without any bad symptoms.'

In this account of the controverfy concerning the fenfibility of bones, cartilages, tendons, ligaments, &c. it fhould, we think, have been hinted, that, fome of the parts fuppofed by Baron Haller, and others, to be wholly infenfible, and which really appear to be fo in a found ftate, have been found to acquire confiderable fenfibility by difeafe; and that an inattention to this circumftance has been the principal caufe of that apparent contrariety of facts, with which this fubject has been perplexed.

That one of the ufes of the fat contained in the membrana adipofa, is, to defend the body in general from cold, and of that in the omentum, to contribute to the warmth of the viscera in particular, are notions fo perfectly hypothetical, and fo generally exploded, that their claim to a place in this work ought certainly to have been rejected.

It is affirmed in chap. 4th under the article of bile, that the • jaundice is most usually produced by obftructions in the liver itself, which by preventing the feparation of bile from the blood, tend to give that univerfal yellownefs to the body, which is the characteristic of the difeafe.' But we are inclined to think, if the Editor had been aware of the weighty objections to which this doctrine is liable, that it would at least have been delivered with lefs confidence.

The opinion, given in the 15th fection of the fame chapter, that the caruncula myrtiformes derive their origin from the rupture, and confequent receffion, of the hymen, is fo ill fupported, either by obfervation or analogy, that we apprehend it would have appeared far better in the form of a conjecture, than in that of a direct affertion.

We fhall now, with a view of giving our readers an idea of this Writers manner, extract his account of the lymphatic fyftem.

The lymphatic veins are minute pellucid tubes, which, like the lacteals, direct their courfe towards the center of the body, where they pour a colourless fluid into the thoracic duct. The lymphatics from all the lower parts of the body, gradually unite as they approach this duct, into which they enter by three or four very large trunks, which feem to form the lower extremity of this canal, or receptaculum chyli. The lacteals open into it near the fame place, and

the

the lymphatics from all the upper parts of the body, pour their lymph into different parts of this duct as it runs upward to terminate ia the left fubclavian vein.

As the lymphatics commonly lie clofe to the large blood veffels, a ligature paffed round the crural artery in a living animal, by including the lymphatics, will occafion a diftenfion of thefe veffels below the ligature fo as to demonftrate them with eafe; and a ligature paffed round the thoracic duct, inftantly after killing an animal, will, by ftopping the courfe of its contents into the fubclavian vein, diftend not only the lacteals, but also the lymphatics in the abdomen and lower extremities, with their natural fluids.

The coats of thefe veffels are too thin to be feparated from each other; but the mercury they are capable of fuftaining, proves them to be very firong; and their great power to contract after undergoing confiderable diftenfion, together with the irritability with which Baron Haller found them to be endued, feems to render it probable, that, like the blood veffels, they have a muscular coat.

The lymphatics are nourished after the fame manner as all the other parts of the body. For even the most minute of thefe veffels are probably fupplied with ftill more minute arteries and veins. This feems to be proved by the inflammation of which they are fufceptible; and the painful fwellings which fometimes take place in lymphatic veffels, prove that they have nerves as well as blood veffels.

Both the lacteals, lymphatics and thoracic duct, are furnished with valves, which are much more common in thefe veffels than in the red veins. These valves are ufually in pairs, and ferve to promote the courfe of the chyle and lymph towards the thoracic duct, and to prevent its return. Mention has been made of the glands, through which the lacteals pafs in their courfe through the mefentery; and it is to be obferved, that the lymphatics pafs through fimilar glands in their way to the thoracic duct.-Thefe glands are all of the conglobate kind, but the changes which the chyle and lymph undergo in their paffage through them, have not yet been afcertained.

The lymphatic veffels begin from surfaces and cavities in all parts of the body as abforbents.-This is a fact now univerfally allowed; but how the fluids they abforb are poured into those cavities, is a fubject of controversy among the anatomifts of thefe times.-The contents of the abdomen, for inftance, were defcribed as being conftantly moistened by a very thin watery fluid.-The fame event takes place in the pericardium, pleura, and all the other cavities of the body, and this watery fluid is the lymph. But whether it is exhaled into thofe cavities through the minute ends of arteries, or tranfuded through their coats, are the points in difpute. We cannot here be permitted to relate the many ingenious arguments that have been advanced in favor of each of thefe opinions; nor is it perhaps of confequence to our prefent purpose, to enter into the difpute.it will be fufficient if the reader can forn an idea of what the lymph is, and of the manner in which it it abforbed.

The lymph, from its transparency and want of colour would feem to be nothing but water; and hence the first difcoverers of thefe veffels ftyled them ductus aquofi-but experiments prove, that the lymph of an healthy animal coagulates by being expofed to the air,

ог

or a certain degree of heat, and likewife by being fuffered to reft; feeming to agree in this property with that part of the blood called the coagulable lymph.-This property of the lymph leads to determine its ufe in moistening and lubricating the feveral cavities of the body, in which it is found; and for which, by its gelatinous principle, it feems to be much better calculated than a pure watery fluid would be, for fuch it has been fuppofed to be by fome anatomifts.

The mouths of the lymphatics and lacteals by acting as capillary tubes, feem to abforb the lymph and chyle in the fame manner as a capillary tube of glass when put into a bafon of water will be enabled to attract the water into it to a certain height.-In the human body the lymph or the chyle is probably conveyed upon this principle, as far as the first pair of valves, which feem to be placed not far from the orifice of the absorbing veffel, whether lymphatic or lacteal: and the fluid will then be propelled forwards by a continuation of the abforption at the orifice. But this does not feem to be the only inducement to its progrefs towards the thoracic duct-thefe veffels have probably a muscular coat, which may serve to prefs the fluid forwards from one pair of valves to another; and as the large lymphatic vessels and the thoracic duct are placed clofe to the large arteries, which have a confiderable pulfation, it is reasonable to fuppofe that they derive fome advantages from this fituation.'

Clear, diftinct, and fatisfactory ideas of the different parts of the human body, can be obtained only by diffection. General notions of them may however be derived from books; and impreffions formerly made on the mind by diffection, may be renewed by accurate verbal description. In this point of view the publication in queftion has confiderable merit. It is written with perfpicuity, and contains feveral modern difcoveries, not to be found in any other compendium of anatomy.

ART. III. A Treatife en Foreft Trees: containing not only the best Methods of their Culture hitherto practifed, but a Variety of New and Ufeful Difcoveries, the Refult of many repeated Experiments, &c. By William Boutcher, Nurseryman, at Comely Garden, Edinburgh. 4to. 15s. Boards. Edinburgh printed, and fold by Murray in London. 1775.

WH

HEN we confider the national importance of keeping up neceffary fupplies of timber, and the private profit refulting from furnishing that fupply, where perhaps the ground will not readily admit of other culture; when we confider alfo how much beauty judicious plantations add to the face of a country, as well as the convenient fhelter they afford, to man, to beaft, to fields, and to gardens; we fhall be convinced that, the public inftructions of fkilful nurserymen, as well as defigners, are intitled to a most welcome reception. It was therefore with pleafure that we faw the refpectable and numerous lift of fubfcribers to this treatife; which feems to promife that Scotland will not long remain under the reproach

fe often caft on it for the want of trees. Dr. Johnson has accounted for this denudation of arborical verdure, by obferving that times of tumult were unfavourable to plantations, and that long established cuftom is not eafily broken: but thefe tumultuous times have long fince ceafed; and from the prefent fpirit of improvement among the Scotch gentry, many of whom have bestowed much praise-worthy attention on planting their eftates, it may be hoped the nakedness of the land will in due time be decently covered.

Indeed the very intelligent nurseryman at Comely Garden, who, as we gather from his own expreffions, was employed for fome years under Mr. Miller, in the Botanic garden at Chelfea, appears to have had the inftruction of his brethren in Scotland peculiarly in view, in this publication; being very severe on the ignorant craft of many of them, who aim rather to underfell the rest of their profeffion, than, by bestowing due culture on their plants, to unite a regard for reputation with views of profit. At the fame time he bestows encomiums on the nurferymen in the fouthern parts of England, which from his knowledge of them, may be fuppofed to be well founded.

• The fuperiority which our Author claims, in his methods of propagating and raising young trees, appears to confift principally in fucceffive plantings, and his treatment of the roots under these operations. A perfon in his clofet might be apt to dread that he removed them too often, and made too free with the roots: but opinions ought ever to yield to experience, and to be formed from it. Doubts on this point might nevertheless receive fome ftrength from a remark of his own, page 43, where treating of the oak, after four or five transplantations, he adds, they will grow as luxuriantly as if they had ftood in the fame foil from the fmalleft fize, and arrive as foon at full maturity." The obvious conclufion from thefe premises is, that had they been left in the fame foil from the smallest fize, all the sublequent labour might have been faved: but the advantage from his culture, is that the trees, from the regular and timely prunings they have had, muft of course be formed to their proper hape, and will require little or no farther trouble:' he had before told us, that no tree requires more address, to make a handfome well-proportioned free growing plant, than the oak.' We must confefs we have no experience to oppofe to what is here advanced.

The following paffage, though it contradicts a popular opinion, will perhaps be affented to, as an article of theory, with lefs hesitation than the propriety of fuch repeated transplantations:

It has been an almoft univerfally received opinion, that trees ought to be raised in the nursery on a poorer foil than that to which they are afterwards to be tranfported for good; and it