By Geo. E. Woodward, Civil Engineer And Architect, No. 20 Broadway, New York.

If there is a department of Landscape Art more noted than any other for its frequent failures, it certainly must be the construction of Terraces. With the established prejudices in favor of the old school straight-line Terrace, and the prevalent primitive notions of their construction, there should cease to be any surprise if failures are common.

Terraces were originally introduced as a connecting link between the bouse and grounds, and we must confess that, in spite of the adoption of the natural style of landscape treatment, the architectural Terrace, in connection with the house, has, to our mind, a grand and imposing appearance. It can never be, or rather ought never to be wholly abandoned, where a display of high landscape art is contemplated.

Another important use of the terrace in the artificial, or, as it is sometimes called, the geometrical style of Landscape Adornment, was for the purpose of joining plateaus of different elevations, these plateaus sometimes being essential to the proper artistic harmony of formal lines, the waving undulating lines of natural surfaces having nothing in common with rigid architectural forms. It is necessary that angles and straight lines be confined to either level or slightly inclined planes, else, by their strong contrast to natural lines, they become offensive to the eye; therefore, it was necessary to break up or separate plateaus by terraces, or reduce them by much labor and expense to a common grade.

The terrace is also made use of in the protection and embellishment of hillsides, and it is in this manner that we propose to treat it. The formal terrace, when used for this purpose, possesses too many elements of weakness to be of permanent value, and the same cause of insecurity is applicable to the whole or any portion of it, if constructed throughout its length of earth of the same character, it being by no means an unfrequent occurrence for the upper terrace, when surcharged with water, to yield for the whole distance, and to destroy or carry with it those below. The construction of straight-line terraces on hill-sides, in addition to their unsuitableness as reliable earth-works, are, except under unusual circumstances, a matter of great expense, and among the knowing ones very generally avoided; they have become, along the Hudson more particularly, proverbial for their expense and insecurity. The proper management of earth slopes and embankments is ranked among the skillful attainments of the educated civil engineer. yet the rural community labor under the impression that an expert vegetable physiologist is by far the most competent person to deal with those difficulties which require, in others, almost a life-long devotion and experience to surmount.

There is, however, a form of terrace that recommends itself strongly to the notice of those who find a pleasure or necessity in beautifying and protecting steep slopes, a form entirely in harmony with the undisputed beauties of the natural style of Landscape Adornment, and one that possesses in a great degree the elements of strength, and the charms of beauty, variety, and economy. We allude now to the natural terrace, as shown by the receding stages of running water, and best illustrated among the alluvial valleys of the West, a portion of our country that presents some of the most magnificent natural examples of the beautiful in Landscape any where to be met with.

The peculiarities of natural terracing are, its incurvate and recurvate outline, a constant variety in the length, character, and direction of the curves, a harmonious change in each successive terrace, adapting itself to the sinuation of declivities, requiring but little removal of earth to form a graceful contour, and possessing conditions of strength unapproachable in either the right line or the angled terrace.

Among the leading charms of landscape embellishment, variety should be well considered. One of the most fruitful sources of variety lies in the proper management of light and shade; and wherever the bold and ever-varying effects of shadow can be controlled, it is the duty of the landscape artist to avail himself of it. The natural terrace affords the opportunity for an artistic display of light and shade which is constantly changing in effect, the strong shadows of the recesses throwing into relief the prominent points which catch the light; it also contemplates the use of embellishments not often made use of on terraces, such as ornamental trees and shrubs, singly or in masses, the gay addition of flowers, the close-shaven and neatly-kept lawn, or for the more practical and quite as enjoyable pleasure of cultivating the Grape, for it should be understood that good taste exacts no such requirements as are deemed necessary, or at least practiced, in the old school terrace, viz., that a succession of terraces should be exactly parallel, and of the same height and breadth, and not devoted to any very useful purposes, a doctrine not recognized in any natural examples.

The strength of the natural terrace is of a character that can scarcely admit a doubt; the salient curves become like buttresses to a wall, and whatever force is exerted, instead of being in one direction, as in the case of the straight terrace, is distributed in such a manner that the same cause which might break through one point is powerless in others: the conditions of security are such that they do not depend on each other.

The judicious use of the natural terrace will obviate all of the prominent difficulties of the straight terrace, and if made use of by those who have a knowledge of the proper construction of earth slopes and embankments, there should be no such thing as a failure.