I have seen a luxuriant

years without fallowing or manure. crop of barley growing on land, that had borne a succession of twenty preceding crops, without manuring. This was in an exposed and elevated situation, and upon a hill of magnesian limestone, which has been frequently referred to by chemical writers as peculiarly unfavorable to vegetation. The limestone of this hill contained twenty per cent of magnesia.

The temperature requisite for the growth of plants is influenced by the power of different soils to absorb and retain heat from the solar rays, which depends much on their moisture and tenacity. It is a well known fact that the vegetation of perennial grasses, in the spring, is at least a fortnight sooner on limestone and sandy soils, if not extremely barren, than on clayey, or even deep, rich soils. It is equally true, but not perhaps so well known, that the difference is more than reversed in the autumn. This effect is ascribed by Egremont, with much probability, to the rich or clayey soils absorbing heat slowly, and parting with it again more reluctantly than the calcareous soils, owing to the greater quantity of moisture in the clay, which is an imperfect conductor of heat. Calcareous soils might be frequently much improved by a mixture of clay, sand, or gravel, which in many situations is practicable with little expense, and would well reward the labor of the experimental agriculturist. Thus far Bakewell's Introduction, which should be attentively read, as containing a condensed view of the essentia principles of agriculture.

Many of the American soils possess, from the bounty of nature, an inexhaustible fertility. Such are belts along most of our larger water-courses, as the Hudson, Mohawk, Susquehannah, Delaware, Ohio, Mississippi, Missouri, and Illinois. We may add to these, the broad alluvial belts of the rivers of the Lower Mississippi. These soils are black, dark-brown, gray, or red, and, in many instances, the vege table stratum is fifty feet in thickness.

That our soils are yet too fresh and fertile to require these laborious processes of manuring, intermixing, irrigating, or

draining, deduced from a scientific application of geological knowledge, is no reason why this most useful and delightful of all studies should not be philosophically pursued. Who can be so dead to all noble and useful curiosity, as not to be stimulated to inquire into the secrets of Nature's store-house, in virtue of which researches, he may be enabled to teach her how to fill her horn of plenty, and put forth her grand variety of vegetation? Who will fail to recollect, that there is in our language a word of such terrible import as famine? Who can forget that this most excruciating of all earthly tortures is an infliction upon beings with the same sensibilities, organs, and dimensions with ourselves; that millions have suffered this living death, and that gray-headed parents have thus perished within hearing of the cries of their famished children? Who would not wish to learn how to draw the nutritive sustenance of life more abundantly from the bosom of our common mother?

I would not deem so poorly, even of the gayest and most fashionable among our young readers, as not to suppose that they will be interested in that science, which teaches to clothe the fields and gardens with beauty and abundance, to rear and feed the nations of bees in their fragrant realms, to make the lambs bound upon the hills, and the valleys to stand thick with corn. It is the most cheering, uncloying, healthful, and satisfactory of all human pursuits, rendering the husbandman nobly independent of all but God; the pursuit, in which the ambitious, the worshippers of the world, fortune, and pleasure, after being worn with their inanity and disappointments, generally choose to end their days under the rustling of their own shades, and listening to the hum of their own bees, and the cheerful sounds of their own domestic animals.

In no country is it so easy to become an independent and happy husbandman, as in ours. Uncounted millions of acres of exuberant fertility invite him to select his farm, and rear his cabin in the shade of his own trees. There let him find his dulce domum, the spot endeared to him by the associations of beauty and abundance won by the labor of his

youth from the barren luxuriance of nature, by the smiles of his spouse and the gambols of his children under his own free bowers, where none can molest nor make him afraid. There let his days flow in useful labor, and the perpetual festival of rendering the family that binds up the bundle of his chief charities, satisfied and happy; in communion with nature and nature's God, ripening to be transplanted from the paradise formed by the industry of his own hands, into the Paradise of God.

After every thing else has been tried to satiety, and has been found labelled 'vanity and vexation of spirit,' this pursuit soothes, satisfies, keeps back premature wrinkles, dyspepsia, and organic affections of the heart.

LECTURE XLVIII.

GEOLOGY. -WRITERS UPON THE SUBJECT. ORGANIC REMAINS.

I CANNOT but suppose that you will be sufficiently interested in this subject, upon which I have but touched, to wish to know where you may prosecute your researches, in a more ample and thorough investigation. I know of no book, which I think a person, commencing the study of geology, will read with so much pleasure and profit, as Bakewell's Introduction to it. He is plain, practical, sensible, and full of instruction. Among the earliest systematic writers upon geology, were Burnet and Lister. Hutton and Werner were the heads of the old school of geology, as Lyell, Fitton, and Sedgwick, are of the new. The works of De La Beche, Brande, Conybeare, and Ure, are mentioned with praise, and are worthy of an attentive perusal. Dr Buckland's work upon the organic remains of the English caves, is an eloquent and instructive book. Buffon, Cuvier,

Blainville, Jeffroy, and Desmarest, are celebrated French writers upon this subject.

In America, this noble science has but recently begun to excite attention, though no country offers a more interesting field, or a more ample harvest. Yet we have already had our Maclure, Silliman, Troost, James, Schoolcraft, Featherstonehaugh, and many other respectable names of geological writers. We have the most ample promise, with such precursors as guides, that this elder and enduring scripture, the bosom of the earth, that feeds and clothes us while we live, and piously shelters our remains when we die, will find faithful and successful interpreters, who will discover in this record of God's past dealings with the world, new grounds of confidence, and new reasons to love and trust him for all the periods to come. I return to a few brief details of the history of organic remains, with which I propose to close an article, which I have been fearful I should have rendered tedious had I gone extensively into its details, or dealt much in its copious and difficult nomenclature.

I have already remarked, that human skeletons and bones have been very rarely found imbedded in secondary rock formations, and even those of coal and peat. It is a strange fact, that the remains of monkies of any class are still more rare. But the quantities of other organic remains of all the animals at present known, and of many that do not now exist, are prodigious. If every portion of our earth that has once been life, were to burst in one re-animated resurrection from the soil, what a spectacle would the face of our earth exhibit !

It is a common error in the Mississippi Valley, to suppose that the bones of the largest and most remarkable of ancient herbivorous quadrupeds, the mammoth, have been found only in this region. Professor Pallas affirms, that from the Don and Tanais, in Russia, to the remotest shores of Siberia, there is scarcely a river in the banks of which the bones of this animal are not abundant. Two large islands near the mouth of the river Indigerska, are said to be composed of the bones of the mammoth, intermixed with ice and sand.

Mixed with them are the bones of the rhinoceros, and of various other huge animals.

The body of a fossil elephant has there been found entire, with the flesh preserved by being buried in ice. It had a mane along its back, and was covered with coarse, red wool, protected by a kind of hair, indicating that it was an inhabitant of cool climates. This animal was from fifteen to eighteen feet high. Bones and teeth of the mammoth are not unfrequently found in England in beds of diluvial gravel and clay, and in caverns. The bones of the rhinoceros are found, with those of the fossil elephant, in Siberia. In the year 1771, the entire body of one of these animals was found in the frozen sands of that country. Bones and teeth of the hippopotamus are discovered in England, France, and Germany. Bones and teeth of a large animal, called the mastodon, are dug up both in Europe and America. The great mastodon had pointed grinders, was a native of North America, and equalled the elephant in size, and resembled that animal in many particulars. Its bones, and even entire skeletons, have been abundantly met with in those salt marshes, known in the western country by the name of licks. Parts of the flesh and stomach have been discovered with them, and in their stomachs certain plants, the names of which are known in Virginia.

No place has yielded such ample supplics of these bones, as Big-bone Lick, in Kentucky. It is a marsh of muddy and alluvial soil. Salt water oozes up from this soil, diffusing a briny sapidity through the clay that attracted immense numbers of the former animals of the country to it, which, by their licking the earth for salt, gave its name to the place. A thousand beaten paths, like those about barn-yards, led to it in every direction. Here are the deposits of the bones of whole generations of these animals. They lie imbedded in the alluvial soil, from four to ten feet in depth. Immense quantities have been dug up, of which part have been carried to Europe, and the remainder appear in greater or smaller quantities, in almost every museum in the United States.