DRAINAGE METHODS FOR COUNTY ROADS. 23 
after it is placed as can be dor.e without marring the surface, and keeping the 
canvas wet constantly. After about 24 hours the canvas may be removed and 
replaced with an earth covering about 2 inches thick. This earth covering 
should be kept moist by periodic sprinkling during the two weeks it remains on 
the pavement. 
BRICK GUTTERS. 
Brick gutters may be constructed in a manner similar to that 
described for cobble gutters, or they may be made as a part of the 
road surface, as in the case of the second type of concrete gutter 
described. They are used seldom on country roads except in con- 
nection with brick pavements, and need not be especially discussed 
here, as the method of constructing the gutters should not be essen- 
tially different from that prescribed for the pavement. 
BRICK GUTTER 
D=-g- Cross-section is segment of a circle. 
Use vitrified brick. 
Sand bedding about 2" thick. 
Foundation of grave! or broken stone. 
Fig. 7. 
COST OF GUTTERS. 
The cost of constructing gutters varies to a very great extent and 
depends principally on the design of the gutter, the construction 
methods employed, and the availability of materials. The amount 
of work to be done may also, of course, have an important influence 
on the unit cost, because this feature determines, in a great measure, 
the manner in which a force of laborers should be organized for 
carrying on the work. If the special conditions affecting any par- 
ticular case are. properly considered the following data should af- 
ford a fairly reliable basis for preparing cost estimates for the three 
types of gutters discussed above. 
First, consider a cobble gutter of the cross section shown in figure 4. the 
foundation to be of crushed stone or gravel and the joints to be filled with 
Portland-cement grout. 
Materials required for 100 linear feet : 
Foundation, 0.20 cubic yard crushed stone or gravel. 
Sand bedding, 0.07 cubic yard sand. 
Cobble paving, 0.15 to 0.20 cubic yard cobblestones. 
Grout, 05 to 0.08 barrel of cement. 0.20 to 0.30 cubic foot of sand. 
Second, consider a concrete gutter of the circular section shown in figure 5. 
