A TALK ON ROAD-MAKING. 



529 



proportionately higher, so that in all cases the water will 

 find its line of quickest descent toward the gutters, and 

 never parallel with them. When newly finished, the 

 crown is better too high than too low, as it will constant- 

 ly be wearing down under the travel upon it. 



Paved gutters to carry off the surface-wash are of the 

 utmost importance wherever the grade is steep or the flow 

 likely to be large under a heavy rainfall. If the grade 



;.— Cross-section of Road-eed. 



be less than one foot per hundred, gutters may not be 

 necessary. Well-laid Macadam stone will stand a heavy 

 flow on an easy grade. The width and depth of the 

 paved gutters will vary in proportion to the amount of 

 water to be carried off. If they are not large enough the 

 water will quickly gouge out another gutter in the Maca- 

 dam along the inner margins. The best work is done 

 with regular blocks, laid lengthwise, as in the best street 

 pavements, but where good cobble-stone is cheaper it may 

 be used. All gutters should have a bed of sand at least 

 12 inches deep. 



The proper laying of underdrains in connection with 

 fine roadways is a matter of great importance, for it 

 largely effects questions of construction and maintenance. 

 If provision be not made for carrying the heaviest rain- 

 falls from the roads, frequent damage of a very aggrava- 

 ting character will be done by severe thunder-storms. 

 It will be cheaper in the long run to provide ample drain- 

 age at first. This is a problem that may require elabor- 

 ate engineering calculations, and some competent expert 

 should be engaged for the purpose. 



Catch-basins, such as are shown in fig. 4, to carry ofl 

 the wash of the road-gutters into sub-drains, should be 

 placed alongside the road at frequent intervals. The 

 overflow drain should be near the top of the basin, the 

 bowl of which should be deep enough to hold all the 

 heavier silt of each storm-flow. The inlet gratings should 

 be fine enough to keep out coarse drift, liable to choke up 

 the drain, and yet open enough not to close up readily 

 with fine grass, dead leaves and other light refuse always 

 abundant in a cemetery. The road-drain should be 

 placed where it will not only carry off the surface-water, 

 but also be most effective in draining the subsoil. Where 

 the subsoil is liable to become water-soaked at certain 

 seasons of the year, the road-drain may be placed along 

 one margin of the drive and a small pipe, for sub-drainage 

 only, be laid along the opposite side. 



The proper care of the road under ordinary wear and 

 tear is as important as its thorough construction. The 

 old adage of the thrifty housewife, that "a stitch in time 

 saves nine," may be applied to a Macadam road without 



any great wrench of metaphor. We have only to think 

 of a rut as a rent, and then we can say fitly that as soon 

 as one is seen it should be stitched immediately, or the 

 whole fabric will soon be ripped up. Wherever a rut 

 deep enough to guide a wheel is seen, all horses and 

 drivers will instinctively fall into line and follow its lead. 

 All wheeling on the road will thus be confined to the few 

 inches in width covered by the two tires. The grooves 

 will deepen with won- 

 derful rapidity. Every 

 shower will wash them 

 out, and heavy rains 

 will gouge them into 

 v^atercourses of what- 

 ever size the flow may 

 require. After rents are 

 patched up the seams 

 will long remain, as 

 travel will shun them because they are rough and softer 

 than the body of the road. 



To maintain a smooth surface, regular sprinkling is 

 necessary in dry weather. It is needed not only to lay 

 the dust, but also to prevent the surface from breaking 

 up. In a long drouth the grit and gravel will be loosened 

 by the horses' feet for several inches in depth, and the 

 particles will be rapidly ground into powder. The sur- 

 face may be kept comparatively whole by simply keeping 

 it uniformly moist. 



On the other hand, in wet weather, it is equally impor- 

 tant to scrape off the mud. A muddy road is not merely a 

 dirty one. Wherever there is mud enough to be sticky it 

 will be lifted with the tires, and much grit will be picked 

 up along with it. The mud also prevents water from 



Fig. 4.— Catch-basin and its connection wiih drain 

 under road-gutter. 



running off freely, and it is soon worked into slush. In 

 such condition all travel on the road is abominable. The 

 adhesion of the Macadam stones is also soon destroyed 

 by the constant churning of the surface and the softening 

 of the matrix in which they were bedded. 



