its outer line relates to the view beyond, not concealing too much or intruding a too formal foreground. Its height above the surface below will be motived by the relations of its bank or retaining wall - perhaps with its steps or niches or other decorations as the case may be — to the composition offered in a view towards the building, by its proportions for itself, and by its relation as a base to the building. A series of terraces running down a hillside should have adequate termination, both at the ends of each separate terrace and at the bottom of the scheme. The relative shapes of such terraces should be carefully studied so that their successive surfaces may be seen in pleasant proportion from above and their successive walls may surmount one another in pleasant relation as seen from below, and culminate effectively in the dominating structure. For these purposes an ideal arrangement of terraces would be one in which the upper terrace next the building was narrow and high, and the height of the successive terraces decreased and their width increased to the terrace at the foot of the series, which might be broad and low. In formal arrangements of the ground like those in a formal garden, importance may be given to one part of an area by arranging it as a terrace, as for instance where one end of a garden is so treated and a banqueting house or shelter built on such an elevation. Or the concavity of the whole form of a garden may be accented by a slight terrace running all the way around it. Since people will, if it is possible, invariably come to the very edge Parapets of any elevation on which they stand to enjoy a view, there should usually be a path along the outer edge of the terrace, and, if the fall be at all considerable, a parapet of some kind on which the visitor may lean. If the design requires it, this parapet need be no more than knee high, but it will still be effective if it be broad enough. At the head of the curving flight of steps above the tapis vert at Versailles, where a parapet would have been undesirable on account of the view towards the chateau, the safety of spectators is practically assured by an evergreen hedge planted on the lower level, with its broad top, trimmed flat, reaching to the upper level. A terrace parapet can hardly exceed a height comfortable to rest the elbows on without seeming out of scale with the size of a man. The question of the construction of the parapet balustrade, pierced wall, post and panel, or whatever else of all the Retaining Walls Terrace possible alternatives may be chosen - is one of architectural detail which we cannot cover here. The most definite and architectural form of terrace is produced by a retaining wall crowned with a properly proportioned balustrade and perhaps paneled with piers or buttresses. Especially where this wall is not very high, the proportion between the wall and the parapet becomes a matter of great importance. If these proportions, as they are forced upon the designer by the normal height of a balustrade and the necessary difference in elevation of the ground, are not satisfactory, they may be improved to some extent by a judicious choice of the height of the base-course for the wall or of the crowning course on which the base of the parapet is set. If no solid parapet and no stone balustrade can be arranged in good proportion, it may still be possible to construct a light iron grille-work which will serve all purposes of safety without assuming importance in the design of the wall, and without intruding on the view from the terrace itself. Where there is a possibility that a long straight run of terrace wall may prove monotonous, it may be broken by projections which offer particularly good viewpoints and which serve some subordinate purpose of their own as objects in the design. The face of a terrace wall is almost always broken by steps at some place, and indeed the case seldom arises where the designer cannot obtain sufficient variety of shape in a terrace by recognizing local requirements, and this without appearing to have willfully distorted the shape of the structure. A terrace wall is an ideal backing and protection for herbaceous planting, as can be seen in many examples of the English borders. Where, for reasons of economy or design, it is undesirable to support a terrace by a vertical retaining wall, a sloping bank may be used with its surface held in place by turf or possibly by other planting. If the terrace is to retain its architectural character, some fine-textured covering material like turf will be essential, in order that the surfaces and lines of the bank may remain sufficiently defined. From the practical point of view, the slope will be determined by the angle of repose of the material and by the possibility of cutting the grass: a slope steeper than forty-five degrees is likely to be hard to maintain.* * Cf. Natural banks, Chapter VIII, p. 148. From the point of view of appearance, the big general mass relations of the scheme will have the preponderant influence, but an important minor consideration is the parallelism between the surface of the bank and any flight of steps which may lie upon it. This would give the bank a slope of about one on two. The turf terrace bank has perhaps its best use where different levels are to be individually defined, but still very definitely recognized as parts of one larger open area. Planting at the top of such slopes may be desirable and can be effective; even architectural balustrading at such a place is occasionally good. Planting directly at the bottom of these slopes is, however, extremely hard to manage the slope itself, as we have seen, cannot readily be planted, and if it be kept in turf, it makes an open space behind planting at its foot which is likely to make this planting appear as if it had insufficient background. Steps leading from one level to another in a landscape design are, Steps like gateways, objects which have or seem to have an economic use, and so a certain feeling of inevitableness in the scheme, but which are also extremely desirable objects in the esthetic design. They diversify and enrich the walls or banks of terraces; they lie naturally as terminal objects and vista points to walk towards, and centers of pictorial compositions to look at. From the necessary relation of the riser and tread of their steps* and the relation of the height of their balustrades to the height of a man, they introduce an element of human scale into the composition and a pleasant suggestion of human use. Flights of steps are often more effective when supported by larger objects. They may run down by the side of a projecting building or retaining wall, agreeably filling in and softening what might be otherwise a harsh angle. They may, however, themselves assume dominant importance in a view, forming architectural objects of almost any degree of interest and complication. When steps are treated as important objects in this way, two interrelated considerations are likely to be paramount: their architectural form and the directions of traffic and views to and from them. Where the line of traffic and view is continued unchanged beyond the steps in each direction, or * See article by F. L. Olmsted, Jr., Notes upon the Sizes of Steps required for Comfort, with diagram, in Landscape Architecture, Jan. 1911, vol. 1, p. 84-90. Steps in Formal Design where the traffic is turned abruptly at the foot of the steps, or the traffic and the view stop short or turn abruptly at the top, a single straight flight of steps will probably be constructed. There will be a tendency to make the width of the flight of steps equal to the width of the path which approaches them, but considerations of the total mass of the flight as an object in the design will enter here, and if it be not very high, it may for this reason be made wider. Or the mass may be considerably increased by posts, balustrades, ramps, or projecting bases for flower pots at the sides of the steps. If the steps lie in a turf bank, it is usually desirable to have the line of the nosings of the steps lie in the plane of the bank or at least be parallel to it. Balustrades on such steps are not practically necessary and are usually not esthetically desirable. A low ramp paralleling the slope of the bank, or perhaps a stepped ramp is more likely to be congruous with the shape of the bank. Where a single flight of steps leads to an open panel below or to walks that go in several directions, the steps, or at least the lower part of the steps, may well recognize this dispersion of traffic by a rounded or splaying form. Such a form has an obvious esthetic advantage in design, since the broader lower steps give a pleasing base to the whole flight and lead the eye agreeably from the rising line to the horizontal surface below; but nevertheless such forms should be used only with great care unless the lower area to which the steps lead has considerable openness and expanse to right and left of the steps. One line of traffic below may be spread into two lines above by balanced flights of steps rising to right and left. Such an arrangement almost necessitates something — niche, fountain, or similar feature — in the wall between the steps at the lower level, terminating the single lower path and enframed by the balanced flights of steps. This arrangement is usually best when it is sunk into the face of the retaining wall, rather than when the landings at the tops of the two flights of steps form projecting bastions. Two lines of traffic below may be collected into one line above often by two balanced flights of steps applied as it were to the outside of the retaining wall and projecting above in a bastion for the top landing, or by two flights of steps, usually curving, sunk into the body of |