The time occupied in loading a barrow will vary with the character of the material and the proportion of wheelers to shovel lers. Approximately, a shoveller takes about as long to fill a barrow with earth as a wheeler takes to wheel a full barrow a distance of about 100 or 120 feet • on a horizontal plank and return with the empty barrow.
Carts. The cart usually employed for hauling earth, etc., is shown in Fig. 39. The average capacity is 22 cubic feet, and the average weight is 800 lb. These carts are usually furnished with broad tires, and the body is so balanced that the load is evenly divided about the axle.
The time required to load a cart varies with the material. One shoveller will require about as follows: Clay, seven minutes; loam, six minutes; sand, five minutes.
Dump Cars. These cars are made to dump in several different ways, viz., single or double side, single or double end, and rotary or universal dumpers.
Dump cars may be operated singly or in trains, as the magni tude of the work mty demand. They may be moved by horses or small locomotives. They are made in various sizes, depending upon the gauge of the track on which they are run. A common gauge is 20 inches, but it varies from that up to the standard railroad gauge of 56- inches.
Dump Wagons. (Fig. 40.) The use of these wagons for mov ing excavated earth, etc., and for transporting materials such as sand, gravel, etc., materially shortens the time required for unloading the
ordinary form of contractor's wagon; having no reach or pole con necting the rear axle with the center hearing of the front axle, they may be cramped short and the load deposited just where required. They are operated by the driver, and the capacity ranges from 35 to 45 cubic feet.
Mechanical Graders are used extensively in the making and maintaining of earth roads. They excavate and move earth more expeditiously and economically than can be done by hand; they are called by various names, such as "road machines," "graders," "road hones," etc. Their general form is shown in Fig. 41.
Briefly described, they consist of a large blade made entirely of steel or of iron, or wood shod with steel, which is so arranged by mechanism attached to the frame from which it is suspended that it can be adjusted and fixed in any direction by the operator. In their action they combine the work of excavating and transporting the earth. They have been chiefly employed in the forming and main tenance of earth roads, but may be also advantageously used in pre paring the subgrade surface of roads for the reception of broken stone or other improved covering.
A large variety of such machines are on the market. The " New Era" grader excavates the material from side ditches, and