in a successful oval turn. The first is that a machine may traverse it comfortably at a speed of not over eight miles an hour without encroaching on the edges. This is more easily accomplished if the roadway of the oval is given a slope or “bank,” high on the outer edge, rather than crowned, as in the ordinary road. The second is the provision of ample space for a standing and passing car before the steps by making the drive at this point not under fifteen feet, and preferably sixteen or seventeen feet in width. (Figs. 14, 12, 3, 7.) The third is the widening of the drive on the semi-circular curves to allow the rear wheels to take a shorter radius than the front wheels without going beyond the edge
of the road surface. (Fig. 2.) The fourth is the allowance of sufficiently easy curves adjacent to the steps, so that the rear door of the car may be readily brought parallel with, and close to, the house steps for convenience of receiving and discharging passengers.
In Figure 1, the oval turn is shown in its simplest form and dimensions, and is especially interesting in giving a comparison of size and shape required by the auto as compared with the old loop, as indicated in dash line, which was designed for horse-drawn vehicles. While a maximum diameter of 52 ft. answered for the horse turn, 67 ft. is allowed for the auto turn.
A loop is rarely best in the form of a circle, and the reasons have largely to do with limit of area. An oval with entrance steps on the long side occupies much less space than a circle which would give equal ease in bringing an automobile parallel with the steps. This is quite evident on reference to Figure 2. This is a typical and ideal front entrance turn on a large estate where no complications occur and the area need not be restricted. If the radius of approach to the steps were the radius of a circular loop, it would require a diameter of 160 ft. in place of the 77 ft. required by the oval. Figure 2 shows the type where the service road branches from the main drive before the loop
Photo 15. Looking into the entrance and garage turn from a point opposite the entrance steps. See A, fig.
No. 14.
Photo 13. The garage placed at an angle to provide space for planting seen in left of picture. See fig. No. 11.
Photo 18. Entrance drive parallel with side of house and framed with newly transplanted trees and shrubs. See fig. 14, photo 15.
of the road surface. (Fig. 2.) The fourth is the allowance of sufficiently easy curves adjacent to the steps, so that the rear door of the car may be readily brought parallel with, and close to, the house steps for convenience of receiving and discharging passengers.
In Figure 1, the oval turn is shown in its simplest form and dimensions, and is especially interesting in giving a comparison of size and shape required by the auto as compared with the old loop, as indicated in dash line, which was designed for horse-drawn vehicles. While a maximum diameter of 52 ft. answered for the horse turn, 67 ft. is allowed for the auto turn.
A loop is rarely best in the form of a circle, and the reasons have largely to do with limit of area. An oval with entrance steps on the long side occupies much less space than a circle which would give equal ease in bringing an automobile parallel with the steps. This is quite evident on reference to Figure 2. This is a typical and ideal front entrance turn on a large estate where no complications occur and the area need not be restricted. If the radius of approach to the steps were the radius of a circular loop, it would require a diameter of 160 ft. in place of the 77 ft. required by the oval. Figure 2 shows the type where the service road branches from the main drive before the loop
Photo 15. Looking into the entrance and garage turn from a point opposite the entrance steps. See A, fig.
No. 14.
Photo 13. The garage placed at an angle to provide space for planting seen in left of picture. See fig. No. 11.
Photo 18. Entrance drive parallel with side of house and framed with newly transplanted trees and shrubs. See fig. 14, photo 15.