98 CONSTRUCTION 



more accurately and because the grade stakes can all be 

 preserved until the finished grade is reached. Carts are 

 used for short hauls and wagons for long hauls. 



Excavation by Plow and Shovel. By this method the 

 soil is broken up by the pick- or rooter-plow, whose point 

 is much heavier and longer than that on an ordinary 

 agricultural plow. (See Fig. 26, page 83.) Carts or 

 wagons are used as in the preceding case. It is of course 

 much cheaper to plow the soil than to loosen it by hand 

 providing that the work is of such a character that the 

 plow is available. 



Excavation by Grading Machine. The Austin Excavat- 

 ing Grader is a machine well adapted to topsoil stripping 

 over broad areas. This machine is driven by 12 horses, 

 8 in front and 4 behind, or by a traction engine. It con- 

 sists of a heavy plow which throws up the soil on a revolving 

 belt which carries it up and then drops it in a dump wagon 

 driven alongside. At least two drivers are required and 

 sometimes four at the beginning of operations in order 

 to properly manage the horses. One man is needed to 

 operate the plow. (See Fig. 11, page 37.) 



By Steam Shovel. Where the cuts are very heavy and 

 the work large in amount, it will pay the contractor to use 

 a steam shovel. He will also need a few light locomotives 

 and an outfit of dump cars, and probably one or more 

 centrifugal pumps to keep the pit where the shovel is located 

 free from water. The filling is done from trestles. The 

 settlement will thus be much more than by the other 

 methods where the fill is consolidated by wheels and horses' 

 hoofs. It is not advisable to attempt road construction 

 on filling thus made until thorough settlement has taken 

 place, nor to lay sewer and water pipes, unless tamping 

 has been resorted to. 



