THE second Annual Meeting of the YOUNG MEN'S ASSOCIATION FOR THE PROMOTION OF LITERATURE AND SCIENCE was held last evening, when the following officers were chosen for this year :GEO. S. HILLARD, President; B. B. THATCHER, Vice President; GEO. W. LIGHT, Cor. Secretary; GUSTAVUS HORTON, Rec. Secretary; EDw. BELKNAP, Treasurer.

The object of this Association is, Mutual Improvement and the general promotion of Literature and Science. The Corresponding Secretary will be gratified to receive communications from any part of the country.

A PROJECT is on foot in this city for the erection of a new public building, to be called, probably, the TEMPLE OF EDUCATION, COntaining one large lecture room or more, and several smaller ones, such as the various societies require for their respective purposes. We think the wants of the community call for such a building, and have no doubt that there will be spirit enough to secure its erection.

THE COLONIZATIONIST.-Our friend Thatcher, the Editor of the Colonizationist, is certainly one of the most indefatigably industrious men in Massachusetts. With all the vexations of a daily press, he regularly sends forth this periodical, so well stored with important original matter, that it would lead one to suppose that he engaged in nothing else. It is an excellent work, and should be subscribed for by every man of intelligence.

MUSIC.-Henry R. Cleaveland, Esq.'s lecture, Friday, Jan. 3, before the Institute, on Music, was just what might be expected from a profound scholar. We hope some way will be devised by which the manuscript may get into the hands of our compositor, that all the patrons of this Journal may participate in the exquisite harmony which the audience enjoyed at the Athenæum.

MR. D. J. BROWNE, the Naturalist, who for some time conducted a periodical in Boston, called the Naturalist, is now travelling in Europe. We received a letter from him, not long since, dated at Teneriffe. Extracts will be made from his journal, from time to time, as it comes to hand.

PROF. HITCHCOCK'S REPORT.-We have been waiting many weeks for an elaborate notice of this valuable work, but regret to say that nothing has yet appeared sufficiently satisfactory. Perhaps, as was the case with reviewers of the Mechanic Celeste, of La Place, in England, six men have not yet been discovered, who are capable of doing it justice.

LECTURES ON PRACTICAL ENGINEERING.-We heard Lieut. Park on Monday evening, Jan. 13, at Chauncy Hall, and can cheerfully and heartily recommend his course of lectures to the public. He is a scholar, whose claims should not be undervalued in a city like Boston.

TO CORRESPONDENTS.-Mr. Loring's paper, highly valuable, on Modern Prussia, has been received, and will be in type at an early period.

Dr. Davis's lecture on the early geographical discoveries in America, is on file. We feel greatly indebted to the author.

Remarks on the Natural History of Man, is rather obscured by a hazy atmosphere. We like to have our communications so well arranged that it will not be necessary to carry a pocket compass to find the ideas.

The generic characteristics of the Sepia, genus Vermes-Mulluscus, is on the table. All such articles are appropriate, and will command attention.

Why does not our friend Dr. Willard, of Charlestown, one of our very best writers, send another roll of his ingenious lucubrations? His pen, like the dip of the needle, always points the right way. Dr. Jarvis, of Concord, is a welcome guest.

Matters and things about the anatomy and habits of land tortoises, like the reptile itself, are crawling towards a future number.

Mr. Smith, of New Hampshire, must not be impatient; he is by no means undervalued. His essay will appear in course. Every word from that industrious scholar is weighed in a pair of scales, and readers may always rely upon having a just weight of practical facts.

A Lover of Nature' is love-sick with the dame. There is no such thing as taking philosophy by storm. Be more gentle, prithee! -when the sky falls, you may take larks.

Who will undertake to furnish a catalogue of the Lyceums in Massachusetts ?

SCIENTIFIC TRACTS

FAMILY

AND

LYCEUM.

FEBRUARY 1, 1834.

[Furnished for the Scientific Tracts and Family Lyceum.] ANALOGIES OF VEGETABLE AND ANIMAL LIFE. [CONCLUDED FROM PAGE 49.]

RESPIRATION.

THE lungs of animals are the spongy, soft, light-colored bodies situated in the chest, commonly called lights. They are composed principally of air vessels and cells, and the blood vessels leading to and from the heart. The windpipe is divided at the top of the chest, and one division goes to each lung: these divide again and again, until, at last, the extremely minute tubes terminate in little cells, into which all the air is sent. One set of blood vessels lead from the heart; at first large, and dividing into smaller and smaller tubes, till very minute extremities end in little cells, which are in contact with the air cells from these proceed other minute tubes, which unite repeatedly, till they form large trunks that open into the heart, which is situated between the two lungs, in the middle of the chest, under the breast bone.

The leaf, like the lungs, is mostly composed of a tissue of vessels and cells. The ascending vessels go from the root through the trunk and branches, and in small bundles through the foot stalk to the leaf, where they are distributed to every part of this organ. In a partially decayed leaf, which we find in the autumn, or which we may macerate in water, all the pulpy portion of the skin of the leaf is

gone, leaving only a net-work, which is rigid and open. This is the system of vessels which composes the ribs and all the frame-work of the leaf. The under surface is covered with exceedingly small apertures, through which the superabundant sap is thrown off. The upper side is also filled with almost innumerable little openings, which penetrate through the bark of the leaf to a cell beneath it, into which the air is admitted. These are the air cells, in contact with the sap cells, so small and so closely set together that Mr. A. T. Thompson counted 55,296 of them on a square inch. These leaves constitute the breathing apparatus of the plant, analogous to the lungs in our own bodies, and performing similar functions, as we shall soon explain.

Of the precise nature of the air cells and sap cells in the leaf, and of the air cells and blood cells in the lungs, and of their specific mode of action in both, we are equally ignorant: we only know of certain effects produced on the sap in the one, and on the blood in the other, which are the consequences of respiration.

The blood, having served its purpose of nourishing the body, is returned through the veins to the right side of the heart. It is then loaded with the exhausted particles of the body which have been taken up with carbon, and also with the chyle which was poured into the vein just before it opened into the heart. Before this blood can again be of service to the living body, it must be purified of its carbon, and its new portions must be converted into blood. For this end it is sent into the lungs, into the minute blood cells, and there comes in contact with the air which is in the contiguous air cells. We are continually receiving fresh portions of air into the lungs. In this state the air contains oxygen, but when it is expired it has lost a part of its oxygen, and is loaded with carbonic acid gas. This new combination must come from the blood: and we find that this fluid, which before had a superabundance of carbon, now has lost it, and is changed from the purple hue of the venous blood to the crimson color of the arterial. The carbon of the blood and the oxygen of the air have united together and formed the carbonic acid gas, which

is expired with the air. The blood is changed in its vital properties and rendered fit to nourish the system, and is taken up from the cells, carried through the minute to the larger vessels, and thence back to the left side of the heart, where it is ready for the general circulation.

The sap is deposited in the sap cells of the leaf. Contrary to the venous blood, it needs more carbon. From the respiration of animals and other causes, the air always contains some carbonic acid gas. This is absorbed by the air cells of the leaf, and there it is decomposed, and the carbon and oxygen separated. The former is added to the sap, while the latter is thrown out, and purifies the air. This is the process in the day time and in presence of light. But in the night or in the dark, the oxygen is added to the sap, and the carbon again returned to the atmosphere. But the plant takes up more carbon than it gives out; so that, although it changes the air, yet the specific effect of its respiration is opposite from that of the animal on the air. But the presence of air is necessary for both, in order to enable their respective juices to maintain life. Both have the organs, and carry on the function of respiration.

CIRCULATION OF THE BLOOD.

The whole system of the heart and blood vessels and their operations, are so well described in Tract No. xix, Vol. iii. that it will be unnecessary to go through anything more than a cursory view of the matter, and point out the analogies and descrepancies between this and that in the vegetable, which we will explain the more minutely.

The heart is the centre of the circulation. It is a large muscular bag, with cavities on each side. That on the right side receives the blood from the whole system and sends it to the lungs for renewal and purification, as heretofore described: the left cavity receives it from the lungs and sends it to the whole body. From the left side then proceeds a large blood vessel called the aorta, which is divided, and the divisions subdivided again and again,