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excellently adapted for the purpose to which they are devoted, of conveying that instruction; and as we have ourselves perused them with pleasure, we feel satisfied that they will prove useful and acceptable to all novices in microscopy. The directions are plain and intelligible, and the student who follows the successive steps here offered to him can scarcely fail to understand the uses and mechanism of the microscope. He will occasionally feel tantalized by a reference to specimens and drawings which the author has exhibited to his class in confirmation of his statements; but possibly a future edition may be rendered more attractive by the addition of illustrations; and we trust that in that case the author may feel assured of a sufficiently large sale to justify the pecuniary outlay necessary to secure their being carefully and elegantly executed.

Art. VIII.—Summary of New Publications.

The most bulky volume that we have received during the past quarter is the first of a work by Henry Thomas Buckle, entitled ' History of Civilization in England.' It extends to 854 large octavo pages, which are entirely devoted (we do not exaggerate) to the general introduction. The task which the author proposes to himself is to determine the "connexion between human actions and physical laws," and by that means to fill up "a wide and dreary chasm" now existing between ordinary historians of the social events and the cultivators of physical science. We turn from Mr. Buckle to undertakings of humbler pretensions. 'The Waverley Journal,' conducted by Women, has recently entered into a new phase of its existence, since which it has come under our notice, and we can say of it that it gives promise of co-operating towards the "emancipation" of the female sex, in the best sense of the word. It is devoted to the consideration of all matters bearing upon the moral, intellectual, and social advancement of women. That the managers of the Journal have secured an efficient Editress is amply apparent from the vigorous, truthful, and wellwritten articles which have come under our notice. None can appreciate woman's help in the work of life better than the medical man; in this sense it is a pleasing dnty to recommend the 'Waverley Journal' to the attention of our readers. 'The Dial Register,' a new daily political periodical, has just been started on the joint-stock principle, under Liberal colours, and comes under our favourable notice as an advocate of reform generally, and of sanitary improvements specially. Among this class of works we have to mention the volume of 'Experiences of a Civilian in Eastern Military Hospitals,' by Dr. Pincoffs, who, having had opportunities of investigating the military medical systems pursued in different countries, suggests numerous changes in our own; we hope to be able to revert again to his suggestions. Other popular works deserving special mention, are, a charming Lecture by Dr. Radclyffe Hall 'On Work, Fresh Air, Exercise, essential to Happiness,' delivered at Torquay, with a view to promoting the Early Closing Movement; a volume by Dr. George Spencer Thomson 'On the Structure and Functions of the Eye;' a Lecture 'On the Principles of Moral Insanity,' by John Kitchingp and a compilation by William Dalton, entitled 'A Key to the Adulteration of onr Daily Food.' Medical reform finds advocates in the persons of Dr. Edwin Lee and Mr. J. S. Gamgee; Balneology has a new representative in Dr. Glover, who has published a veTy useful, as well as entertaining and instructive, work 'On Mineral Waters,' comprising very full accounts of the various watering-places in Great Britain and on the Continent; Dr. Stephen Ward ably and succinctly discusses 'The Medical Estimate of Life for Life Assurance.'

A considerable number of papers on Physiological and Pathological subjects are before us. To the former class belong the inquiries by Dr. John Davy regarding 'The Urinary Secretion of Fishes,' those of Mr. Paget into 'The Cause of the Rhythmical Motion of the Heart,' and an elaborate memoir 'On the Pelvic and Thoracic Members of Man and Mammifers,' by Professor Martins of Moutpellier; among the latter we have to enumerate an .essay by Dr. Boling of North America, 'On the Mechanism and Management of Parturition in the Shoulder Presentation;' a paper by Dr. Duncan 'On the Doctrine of the Duration of Labour,' one by Dr. Marcet ' On the Fatty Matters of Human Excrements in Disease,' another by Dr. Lindsay 'On the Influence upon the Lower Animals exerted by Cholera and other Epidemic Poisons;' Dr. Murchison has published a paper, exhibiting great research, 'On the subject of Gastrocolic Fistula;' a paper 'On Exsection of the entire Os Calcis,' by Dr. Carnochan of New York, and a careful investigation into the Structures of the Cysticercus Cellulosa e of the Pig, by Mr. Rainey, conclude this list.

In addition to the work ' On the Microscope,' by Dr. Beale, spoken of among the Bibliographical Notices, we have to mention the first part of an illustrated work by the same author 'On the Clinical Uses of the Microscope;' a good-sized tome 'On Elementary Botany* has issued from the pen of Professor Henfrey, which will be noticed more at length in our January number, to which time we find ourselves compelled to postpone a review of Todd and Bowman's 'Physiology,' which we had hoped to present to our readers in the present number. A large work 'On Hygiene,' by Professor CEsterlen, well known to the subscribers of the Sydenham Society; an important document 'On Syphilisation,' and 'The Minutes of Proceedings of the Quarantine Convention, held recently at Philadelphia,' have reached us respectively from Germany, Norway, and the United States. A fourth edition of Mr. Beasley's useful 'Druggists' General Beceipt-book,' an essay by Dr. Lane 'On Hydropathy,' numerous surgical and philanthropic papers by Dr. Fabrizj of Nizza, whose qualities of head and heart will doubtless insure him a hearty welcome when he again visits this country; the Latin Harveian Oration by Dr. Copland, the Eighteenth Annual Report of the Registrar-General, and the Eleventh Report of the Commissioners in Lunacy, belong to the literary productions to which we would also desire to give a more prominent place than can be accorded to them in the. list of Books Received.

PART THIRD.

©riqtnal Communications.

Abt. L

On tlieFormalion of tlie Skeletons of Animals, and other Hard Structures formed in connexion with Living Tissues. By George Raihey, M.R.C.S., Lecturer and Demonstrator of Surgical and Microscopical Anatomy at St. Thomas's Hospital.

The observations about to be advanced upon the subject of the formatkm of the skeleton rest upon the fact, that by a proper employment of chemical and mechanical means, calcareous bodies can be produced artificially identical in their mode of formation with a multitude of natural products of a like composition, and so similar in their physical and optical characters as not to admit of being distinguished from them even by the aid of the microscope. Several of the artificial formations, in conjunction with similar natural products, have been submitted to the inspection of persons well practised in the use of the microscope, who have foiled in distinguishing one kind from the other.

The following are some of the natural bodies which have been especially examined and compared with the artificial ones:—The minute globular calculi found in the urine of some quadrupeds, especially in that of the horse; the calcareous deposits found in the pineal body, and several other parts of the brain, also in several glandular structures; the globular calcareous particles composing the deepest stratum of the shells of crustaceous animals, as may be well seen, by a proper mode of preparation, in the shell of the crab, lobster, shrimp, <fec.; the most recently-formed layers of the shells of mollusks, as the oyster, muscle, &c.; the otolithes of fishes, especially when in progress of development, or in those of a very small size, as in the young minnow, in which they are about the size of the largest artificial calculi. To these might be added innumerable others of a similar structure and composition.

All these structures—eveti those first mentioned—are classed by physiologists and histologists with organic products, being considered as made up of minute bodies endowed with a vital formative power, and called cytoblasts, nucleated cells, etc., according to the cell-development theory of Schwann and Schleidon.

The chemical and mechanical means, above alluded to, necessary to form the artificial bodies, are—first, the formation of a carbonate of lime, by the double decomposition of a compound of lime and carbonate (sub-carbonate of the old Pharmacopoeias) of potash or soda, each being previously dissolved in a separate portion of water containing, in solution, some viscid animal or vegetable substance, such as albumen or gum arabic; secondly, a density of the viscid medium in which the carbonate of lime i3 formed, about equal to that of the newlyformed carbonate itself; and thirdly, a state of perfect rest of the fluid in which the decomposition is going on for two or three weeks, or longer, according to the size and completeness of the calculi required. *

Now, I may observe that, although the fact is familiar to many, that a crystalline carbonate of lime ia thus formed when the decomposition is effected in common water, yet I believe it has never been noticed that when the carbonate of lime is produced in such a medium as that above mentioned, in the place of being crystalline it is globular, and that, in this form, its molecules possess a most remarkable power of coalescing into large spherical transparent calculi, and also of intimately blending with all such substances as, in its nascent state, it may happen to be brought into contact with—as, for instance, the glass on which it is deposited.

This globular form of the carbonate of lime was first observed by me in 1849, and shown at that time to several of my friends; but I did not notice its other properties, and the extent to which it exists in organic products, until the year 1856.

Now as the various forms of this substance, as prepared artificially, can be shown to be identical with the corresponding forms of the same compound occurring in nature, a clear and comprehensive description of the best method of forming the artificial products cannot fail to be of interest, especially as it will furnish the best and only key to the successful investigation of the real nature and mode of formation of the natural ones. Besides, I may add, that the artificial calculi, when properly prepared, present the inicroscopist with a new class of polariscope objects, probably of all others the most beautifuL After making a great number of experiments, with a view to determine the process best adapted for furnishing these calculi of the largest size and in the shortest space of time, I found the following to be the best formula.

Dissolve a pound of gum arabic in as small a quantity of water as convenient, and, after straining off the solution, mix with it two ounces of carbonate of potash; then set aside the mixture for some days, in order that the carbonate of lime therein formed may subside. Afterwards, filter the supernatant alkaline solution of gum through cloth, and evaporate it by a very gentle heat to the consistency of very thick treacle. The carbonate of lime which is thus formed and deposited is in globular particles of different sizes, but not sufficiently transparent or spherical to be applicable to microscopic purposes. To obtain the more perfect forms of this globular carbonate of lime* put a given quantity of the above inspissated solution, with some more subcarbonate of potash dissolved in it—one ounce, for instance— into a two-ounce wide-mouthed bottle, and introduce into it two microscopic slides of the ordinary dimensions, so placed that their upper edges are resting one against the other, whilst their lower ones are separated as far as the width of the bottle will allow; then pour gradually, so as to disturb this solution as little as possible, into the same bottle a sufficient quantity of weak solution of gum arabic, perfectly clear, and of l-050 specific gravity, entirely to fill it; afterwards, let these remain at perfect rest for three weeks or a month, or even longer, if the calculi are required to be of the largest size and perfectly transparent; and, lastly, remove the slides, wash them in repeated portions of water, and globular calculi will be found attached to their surface. Those on the under surface of each slide will be found to be the largest, most spherical, and to have the greatest transparency. In this process the lime is furnished by the decomposition of the malate and other soluble salts of lime contained in the weak solution, which are in about the proper proportion to produce the largest globules. The calculi are formed in the shortest time when the two solutions differ most in density, notwithstanding an aqueous solution of the alkali will not answer. It must be combined with gum at the time they are brought into contact, otherwise crystals, and not globules, of carbonate of lime will be produced. If the mucilage containing the alkaline carbonate and that containing the salt of lime be of au equal density, they combine very slowly, and the globules are formed slowly; but their structure is very complete if only sufficient time be allowed for the thorough blending of the two solutions. I have found that two or three months will be necessary for that purpose. The most remarkable fact presenting itself in the formation of these spherical calcareous bodies is, that of the perfect coalescence of two or more of them, even after having attained T£j of an inch in diameter, though of an almost glassy hardness, and without any external force acting upon them; but solely in consequence of their mutual attraction one for another. Now in order thoroughly to understand the cause of this singular fact, and the manner in which it acts in producing the coalescence of bodies of such a size and density, it will be necessary to examine very minutely every step of the process by which it is produced. For this purpose, minute portions of two such solutions, of unequal density, as those above described, mast be brought in contact, on a piece of glass, under the microscope, and be examined by high magnifying powers whilst the carbonate of lime is being formed.

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