inertia would be destroyed, and it actually is so, by the springs now at present used, and by the smooth roads."

Extract from an Essay on the Construction of Roads and Carriages, by RICHARD LOVELL EDGEWORTH, Esq., F.R.S., M.R.I.A. Second Edition.

"So great is the advantage of springs, that they almost annihilate the resistance which that par of the load which rests on them would encounter without them, upon stony roads, or rough pave

ment.

"From the whole of these experiments, it appears that the advantage of springs increases with the increased velocity of carriages."-p. 118.

"Indeed the advantage of springs has, from common observation, been stated to be equal to one horse in four."-p. 126.

Upon the whole, the application of springs to carriages, either for carrying burthens, or for pleasure, tends not only to the ease of the travellerto the safety of goods that are carried-to the preservation of roads-and to the duration of carriages themselves, but they also materially facilitate their draught.”—p. 170.

As the throwing the body so far back as has been proposed will not admit of long side springs if four horizontal springs were used behind, it is proposed that there shall be only one cross spring, and that the fore ends of the side springs shall be

fastened to the body of the coach. The fastening of them should be adjusted in such a manner as to make the whole of the weight of the body and hind boot, before they are loaded, press on the parts of the side springs which are behind the axle. By this plan of having only one cross spring the body of a coach will have a much steadier support than it has according to the present plan of two cross springs, and the risk of overturning will be diminished.

The side springs to be 4 feet 6 inches long, the cross spring to be 46 inches.

In order to keep the weight of luggage as far behind as possible, nothing but carpet-bags and light packages should be put into the front boot. As the top of the coach will be only 7 feet 6 inches from the ground, portmanteaus and other heavy luggage may be put upon the roof. If 3 feet 6 inches of the roof next the guard's seat be used for this purpose, nearly the whole of the weight of the luggage on the roof will be over the hind wheels. For still further securing the object of having the weight as far behind as possible, a strong iron should project one foot from the bottom of the hind boot, having an iron frame, 18 inches in length, fastened to it with a hinge, so that extra mail-bags and heavy luggage may be packed to the full height, if necessary, of the top of the guard's seat.

The splinter-bar should be set 3 feet above the ground: this will make the angle at the point of

the shoulder of the horse, between the trace and an horizontal line, an angle of about 15 degrees.

Summary of the foregoing Plan for building a Coach.-(See Plates VIII. and IX.)

1st. The hind wheels to be 4 feet 8 inches high.

2d. The fore wheels to be 3 feet 10 inches high.

3d. The perch to be 6 feet long.

4th. The perch to be fixed under the hind axle. 5th. The axles to be straight from end to end, and the bottom of the hind boot 7 inches above the hind axle.

6th. The rim of the hind wheel to project 4 inches beyond the line of the opening of the coach door.

7th. The breadth of the side panels, between the door and the hind boot, to be 20 inches.

8th. The end of the hind boot to project 4 inches beyond the rim of the hind wheel. The height of it to be 36 inches, and the breadth 42 inches.

9th. The breadth of the door to be 21 inches. 10th. The breadth of the side panel, between the door and the fore boot, to be 20 inches.

11th. The length of the bottom of the fore boot to be 25 inches; the height of it 34 inches; and the breadth of it 36 inches.

12th. The side springs before to be 30 inches, and the cross springs 46 inches.

13th. The side springs behind to be 54 inches long, and the cross spring to be 46 inches. The fore ends of the side springs to be fastened under the body.

14th. The well of the body to be 7 inches below the body, and 29 inches from the ground; the seats 15 inches above the floor of the well; the cushions 4 inches thick. The distance from the cushions to the roof to be 3 feet 6 inches.

15th. The depth of the seats to be 18 inches, and the breadth of them to be 44 inches.

16th. The guard's seat to be 15 inches above the hind boot.

17th. The splinter-bar to be 3 feet from the ground.

18th. The hind irons to be 2 feet 6 inches long.

The advantages of a coach built on the plan proposed, over a coach built on the plan now commonly in use, will be as follow:

1st. By having the fore wheels higher, the weight set as much as possible over the hind wheels, the perch shorter, and the springs longer, the labour of the horses will be very much diminished.

2dly. By making the body wider, deeper, and higher, it will be much more convenient for travellers; they will also have great benefit from the longer springs.

3dly. By fastening the perch under the axle, the body of the coach will be at a less height

from the ground than is now commonly the case.

Comparative Size of a Coach built on the proposed Plan, and of a common Coach.

From this table it appears that great improvements may be made without departing very much from the present plan of building coaches.

As the practice of dishing wheels, and bending the arms of the axles downwards, originated in some degree in the bad state of the roads, now that they have become so much improved the degree of dishing heretofore given to wheels should be