THIRD ANNUAL YEAR BOOK — PART I. 



27 



deep and dangerous from neglect of proper outlets. Careful attention 

 should be given to the regularity of the grade and fall of the side ditches. 



PROTECTION FROM "GULLYING."— Where the road is built on a 

 steep grade some provision should be made to prevent the washing of 

 the gutters into deep gullies. This can be done by paving the bottoms 

 and sides of the gutters with bricks or field stones. In order to make the 

 flow as small as possible in side ditches it is often advisable to construct 

 f*requent outlets into the adjacent fields or streams, or, if possible, to 

 lay underground pipes or blind drains with screened openings into side 

 ditches at frequent intervals. The size of side ditches should depend 

 upon the amount of water they are expected to carry. If possible they 

 should be located at least 3 feet from the edge of the traveled roadway. 



CONSTRUCTION OF SIDE DITCHES.— All side ditches should have 

 a gradual fall of at least half a foot in every 100 feet. Their sides, par- 

 ticularly those sloping toward the roadway, should be broad and flaring, 

 so as to prevent accidents as well as the caving in of their banks. Their 

 bottoms should be wide enough to carry the largest amount of water 

 that is likely to flow through them at any one time. Sometimes the only 

 ditches necessary to carry off the surface water are those made with the 

 road machine. The blade of the machine may be set at any desired angle, 

 and when drawn along by horses or by a traction engine cuts into the 

 surface and spreads the earth uniformly over the traveled way. (Fig. 5.) 



Fig. 5.— Road machine at work on earth road. 



CROSS DRAINS. 



NEED OF QUICK DRAINAGE.— To drain a road surface properly, 

 water should be gotten rid of before it gains force or headway or has 



