Myers' System of Modern Geography.

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tread the wilds of Siberia, to behold the variegated scenery of the western world, or even the groves of Italy.. The great bulk of mankind must be contented with the detail of others, for the knowledge which they possess of foreign and remote regions, and to the patient toils of the geographer, for laying before them an arrangement of the facts which are obtained from actual observation.

The province of the geographer is, therefore, an important one. We augured well of the Geography of Mr. Myers at its outset; but were we to content ourselves with the opinion which we then expressed, we should by no means do justice to the value and importance of the work. It is completed in a manner far superior even to the expectations which we then formed of the undertaking. In fact, it is such a valuable and correct delineation of the present state of geographical knowledge as is no where else to be found. For whilst the Author has neglected no source of information, worthy of being consulted, he has also spared no pains in compressing his voluminous materials into such a form, as will not only fully answer the purposes of the general reader, but repay, with interest, the perusal of the man whose liberal range of knowledge would turn with indifference from superficial detail.

The Introductory matter, containing the history of geography and a general view of the science considered mathematically, physically, and politically, is not one of the least interesting portions of the work; nor are the Observations on the influence of Missionary Establishment, on the advancement of Geography, prefixed to the second volume, less deserving attention. The maps which accompany these volumes are forty-nine in number; the other plates explanatory of the work, containing views of the principal cities, mountains, natural curiosities, &c.

&c. amount to sixty. The printing and paper are of the first quality. In a word it has not often happened that a work has fallen under our notice which we can recommend to our readers with such cordial and complete satisfaction. Our limits only prevent us from giving a specimen: the style is perspicuous and unaffected, the arrangement clear, the information copious. The whole does great credit to the talent and assiduity of Mr. Myers, and is a valuable accession to our national literature.

An Encyclopædia of Gardening, comprising the Theory, and Practice of Horticulture, Floriculture, Arboriculture, and Landscape Gardening, including all the latest Improvements; a General History of Gardening in all Countries; and a Statistical View of its present state, with suggestions for its future progress, in the British Isles. By J. C. LOUDON. Illustrated with nearly six hundred engravings on wood. 8vo. pp. 1488.

THIS is a very useful, valuable, and necessary work; although, perhaps, much originality can hardly be expected on subjects so beaten, as many of them of course are, concerning which Mr. Loudon treats; yet, he has arranged his materials with considerable skill, and brought together a mass of information to be found in no other volume with which we are acquainted. Whilst it is a work of considerable information, as well as of utility, it is, at the same time, one of much amusement; and, we doubt not, will find a place in the library of every intelligent person in the

Loudon's Encyclopædia of Gardening.

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empire. It is pleasing also to be able to state, that Mr. Loudon has availed himself of the best and latest sources of information on the various subjects concerning which he treats, and that modern science and discriminating judgment, are here properly and ingeniously combined.

Although a cyclopædia, it is not alphabetically arranged; and, indeed, the alphabetical arrangement would by no means suit the nature of the subject, nor the materials here brought together. We, therefore, cannot but highly approve the arrangement which the author has adopted.

The first part treats of gardening considered in respect to its origin, progress, and present state among different nations, governments, and climates; this is subdivided into the history of gardening among ancient and modern nations; and gardening considered as to its progress and present state under different political and geographical circumstances.-The second part treats of gardening considered as a science: this is subdivided into the study of the vegetable kingdom; of the natural agents of vegetable growth and culture; mechanical agents employed in gardening.-The third part treats of gardening as practised in Britain: this is subdivided into Horticulture, Floriculture, Arboriculture or planting; and Landscape gardening.--The fourth part consists of the statistics of British gardening these are subdivided into the present state of gardening in the British Isles; and on the future progress of gardening in Britain. To these are added a kalendarial and a general index.

The woodcuts by Branston are useful and explanatory; many of them are ornamental: they much enhance the value of the volume. The practical articles

for the professor, as well as the gentleman gardener, are at once numerous and useful; for these we must refer the reader to the work itself. We might, indeed, have presented our readers with the articles inarching, grafting, budding, &c., as samples of the work, which are clear and explicit; but must deny ourselves that pleasure to make room for another on the process of vegetable nutrition, which we recommend to the diligent perusal of a quondam friend of ours, who is fond of talking on the subject, as well as, also, to the attentive consideration of our readers. The articles inarching, grafting, &c., are elucidated with woodcuts very explanatory of the different processes. Mr. L. tells us that shield budding reversed, L, is now generally considered exploded. We confess that this news surprizes us. We ask, with due submission, how long has it been so, and by whom?

If we have any complaint to make of Mr. Loudon's work, it is, that it is rather too technical; but it is difficult to please readers of every taste and degree of knowledge.

Process of Vegetable Nutrition.

"Elaboration of Oxygen It has been already shown that the leaves of plants abstract oxygen from confined atmospheres; at least, when placed in the shade, though they do not inhale all the oygen which disappears; and it has been further proved, from experiment, that the leaves of plants do also evolve a gas in the sun. From a great variety of experiments relative to the action and influence of oxygen on the plant, and the contrary, the following is the sum of the results.

"The green parts of plants, but especially the leaves, when exposed in atmospheric air to the successive influence of the light and shade, inhale and evolve alter

Process of Vegetable Nutrition.

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nately a portion of oxygen gas mixed with carbonic acid. But the oxygen is not immediately assimilated to the vegetable substance; it is first converted into carbonic acid, by means of combining with the carbon of the plant, which withers if the process is prevented by the application of lime or potass. The leaves of aquatics, succulent plants and evergreens consume, in equal circumstances, less oxygen than the leaves of other. plants. The roots, wood, and petals, and in short, all parts not green, with the exception of some coloured leaves, do not affect the successive and alternate inhalation and extrication of oxygen; they inhale it indeed, though they do not give it out or assimilate it immediately; but convey it under the form of carbonic acid. to the leaves, where it is decomposed. Oxygen is indeed assimilated to the plant, but not directly, and only by means of the decomposition of carbonic acid; when part of it, though in a very small proportion, is retained also, and assimilated along with the carbon. Hence the most obvious influence of oxygen as applied to the leaves, is that of forming carbonic acid gas, and thus presenting to the plant elements which it may assimilate; and, perhaps, the carbon of the extractive juices absorbed by the root, is not assimilated to the plant till it is converted, by means of oxygen, into carbonic acid. But as an atmosphere, composed of nitrogen and carbonic acid gas only, is not favourable to vegetation, it is probable that oxygen performs also some other function beyond that of merely presenting to the plant, under the modification of carbonic acid, elements which it may assimilate. It may effect also the disengagement of caloric by its union with the carbon of the vegetable, which is the necessary result of such union. But oxygen is also beneficial to the plant from its action on the soil: