The objection which has been made to this in the damper climate of England, that by their shade, they prevent the roads from receiving enough of the sun to keep them dry and firm, cannot, we think, have any weight here; and in the summer time, their shade is needed much more here than there. How refreshing to the wearied traveller is the shade of trees, on our hot dusty roads, almost every one has experienced, and has felt willing, no doubt, to contribute his share towards converting these deserts into groves. The elm is the tree generally chosen for this purpose; but we should prefer a variety, which might be easily had, and which, by their variety of foliage, would add much to the beauty, and at the same time neither detract from their utility nor add to their expense.

METALLIC WEalth of the WEST.-This is every day more and more developing itself. A geological report lately made in the state of Tennessee furnishes interesting information respecting the flourishing state of the iron manufacture in that state. A scientific traveller has lately discovered almost literally a mountain of iron, yielding 70 per cent of pure metal. Large masses of pure native copper are also known to exist, at the northwest. What more interesting question can come up before the American people, than in what hands these treasures will at a future day be; and what more certain truth, than that upon education, in its widest sense, and the diffusion of useful knowledge, the decision of it depends-a decision which it is yet in our power greatly to influence.

FLAX SPINNING.-A Brussels paper quotes a letter from Lille, (France) as follows:-"A great establishment is now erecting in this city, intended for spinning flax by machinery. Thus the great problem is solved, for which the Emperor Napoleon offered a reward of a million of francs, and we shall now enter into competition with the English, who eagerly buy up all the flax of our country."

USE OF ZINC.-The New York Mechanics' Magazine, contains an important article on this subject, by Prof. Gale, of New York University. He says that both water and other liquids dissolve their oxyde, which is poisonous and disagreeable to the taste, so that it cannot be used in the form of vessels of any kind. For roofing, it is equally objectionable. “In the first place," he observes, "the expansion of the metal is so great, by slight changes of temperature, that the junctures are exceedingly liable to get out of place from expansion and contraction, so that in the present manner of putting on the metal, the buildings are constantly liable to leak." Two objections to its use arising from its brittleness are stated. 1. "It is so brittle that two sheets cannot be put together by folding, but must be joined in a sort of double coil (the two edges of the adjacent plates rolled up within each other ;) and though this joining, when new, will keep out rain tolerably well, it can never be made to resist the action of melting snow," lying on the roof. 2. This fragility, which is increased in a tenfold proportion by diminishing its temperature, renders it very unsafe; as at a freezing cold, it is almost as brittle as glass-so that any heavy body falling upon the coils which project above the roof, will cause an injury which it is exceedingly difficult to repair. In addition, the oxyde which is gradually formed is as constantly washed off and dissolved by the rains, and the rain-water collected in the cisterns is thereby poisoned, and rendered "almost entirely unfit for all domestic purposes."

THE CHEMISTRY OF NATURE.-The processes by which nature works, in the caverns of the earth, some of which are probably completed only in the course of centuries, must forever remain little understood. It is with labor that man imitates, often poorly, a few of her crystallizations and mineralizations. The following experiment, related in the Scientific Class Book, affords one of the few artificial illustrations, on a small scale, of what is ever going on in nature's great laboratory.

Silica is nearly insoluble in water, and probably in all acids except the hydrofluoric. * When silica is fused with

* *

a large proportion of potupa, a compound is produced readily soluble in water, forming the liquor silicum—or liquor of flints, of old writers. Prof. Liegling of Efurot, having prepared this liquor with a large quantity of water and of alkali, suffered it to stand for eight years in a glass vessel, covered with paper, when crystals of salts of potash were formed at the bottom of the vessel, and the remaining liquid, about two ounces, was covered by a transparent crust, consisting partly of carbonate of potash, and partly of crystallized silica-the latter being so hard as to strike fire with steel.

By some magnificent operations, perhaps of a nature similar to this, the beautiful rock crystal and the precious gems are probably slowly concreted, in the interior of the earth. Thus may have been formed even the massy rocks which form the skeleton of the external globe itself.

FOSSIL TRACES OF BIRDS.-Much interest has of late been excited among the scientific, by the discovery of vast numbers of impressions of birds' feet in the sandstone rocks of the valley of the Connecticut. They have been lately described by Prof. Hitchcock, of Amherst, in the Journal of Science, whence these brief statements are collected. The tracks are not discoverable on surfaces which have been long exposed to the action of the weather, but only where the upper layers have been recently removed. Whole lines of tracks of the same fashion are found, leaving no room to doubt that they were made in succession by the same bird, in walking, the tracks of the left and right feet alternating, being perfectly distinguishable. The tracks of a great variety of species are observed, some of them very large. One specimen is described as two feet long, and the length of the step appears to have been about six feet. Many of the tracks appear on surfaces of considerable slope, and yet present no difference from those on level surfaces, so that it becomes apparent that they were made before the elevation of the rocks to an inclined position.

CHRISTIAN RADICALISM.-We fear Mr. Withington, the author of this book just issued by Perkins & Marvin, will not receive the credit of being so much of a philosopher as this work shows him to be. He writes as a man of the world, and not as the defender of any party, and has ventured to state many important truths which will not soon be very popular. No reasonable man, however, will fail to derive benefit from its perusal.

MORAL AND SPIRITUAL CULTURE IN EARLY EDUCATION.We have received an address delivered before the American Institute of Instruction on this subject, by R. C. Waterston. Were only the spirit imbibed and the principles carried out, which are exhibited in this address, we might hope speedily to see better things with regard to the general state of the world. The writer insists upon the necessity of making moral and spiritual keep pace with intellectual cultivation, as the only means of making man what he ought to be.

THE YOUNG MOTHER.-This new work is a treatise on the physical management of children, by Dr. Alcott, author of the "Young Man's Guide" and Editor of the "Moral Reformer." The subject is one of great importance, and on which the community need a great amount of information. We think no family should be without this book.

LECTURES ON GEOLOGY.-Prof. Silliman's chemical course of lectures has been opportunely succeeded by one on Geology by Dr. C. T. Jackson, an able man in this department, and whose lectures have given great satisfaction. The best thanks of the community are due to such men as these, for their efforts to awaken an interest in the most important branches of science.

NATURAL HISTORY OF WATER.

BY C. T. JACKSON, M. D.

Water essential to organized beings.

Divisions of water.

THERE are, perhaps, few subjects more worthy of our consideration, than the Natural History and Properties of Water-a liquid which enters into the composition of an endless variety of beings belonging to the three kingdoms of nature, and which is essential to the existence of animals and plants.

It is certainly a remarkable fact, that we are prone to neglect those things which are exposed to our daily observation, while we seek eagerly after those which are rich, costly and rare.

I trust, however, although the subject which I have selected for this essay is one of the most common and abundantly diffused substances in nature, that we shall find it a fruitful topic for reflection, which may advantageously engage our minds, and that from its consideration we may derive some useful lessons, applicable to the ordinary affairs of life.

In the course of this essay, I shall notice the great divisions of water; their relation to each other, to man, animals and plants; showing the final causes of some of the most remarkable phenomena. I shall endeavor, also, to give some practical rules for estimating the purity or impurity of water, so that the reader may be enabled to detect, by means of certain tests, the nature of the foreign