The weekly examiner., 1901-04-13
TAR MACADAM PAVING.
Authorities Claim That for Excel lence, Durability and CheapneSa
 1t Has No Equal.

United States Consul F. M. Shepard,
 at Hamilton, Ont, says:
 "After years of experiment this city
 is laying pavement that for excel lence, durability and cheapness is
 commended for examination to those
 in charge of similar work in the United States. The possibility of making good roads at reasonable cost has been demonstrated, and tests extending
 over number of years on business streets prove that tarred macadam
 makes not only a smooth and solid
 roadway, but one that can be kept in perfect repair at nominal expense. The first cost in this city, where lime stone is abundant and near at hand, is from 70 to s6 cents per square yard, and the engineer estimates the cost of repairing on heavy traffic streets at less than one cent per yard a year,
 while asphalt costs over three cents.
 The addition of tar renders the road way imperyious to water, frost-proof in winter and prevents mud and dust in summer. It is easily repaired and does not require scraping, thus avoid
 ing much wearing of the surface.
 "One block of tar macadam laid
 more than year ago on a business street where there is heavy teaming shows no perceptible wear to-day. In residential streets these pavements have been in use eight years without any repairs, and are still in good con dition. The success of this method of roadmaking depends on care in it's
 execution, as in the case of all com posite work of this character, and l submit for the information of those interested the substance of an inter- view with the engineer of public works, E. G. Barrow, covering details of the processes in use here. Either stone or cement curbing should be placed before beginning the roadway. Cement costs here 50 cents per lineal foot and is six inches thick and 20 inches in depth and laid on broken stone or gravel. Corners are rounded and an iron plate imbedded for pro- lection. On business streets stone is preferable.
 'An essential in roadmaking is a hard and compact foundation, which can be secured only by the liberal use of heavy rollers (12 to 16 tons) while the base is being prepared. The grade and camber should be so designed as to carry water off the surface quickly. and all earth above the lsubgrade should be removeds so as to conform to it's leveI-12 inches below the natural ] surface-which subgrade should be l thoroughly rolled and soft spots filled 1 with stone. The foundation must be | compost, a solid bed of stone not less ! than six inches in thickness. If the ! soil is of 8 spongy nature, large, fiat ! stones are preferred. All interstices | should be filled with small stone and | gravel we'll rolled in. Over this coat l ing of gravel should be rolled hd
 and then layer of tar-saturated | stone, not exceeding two inches in | diameter. These stones before being mixed with boiling tar (1O to 12 inn l perial gallons to the cubic yard) must ! be thoroughly dried, either in the sum- | mer sun or by exposure on heated ! plates, until all moisture is expelled.
 After thorough rolling another 1 stratum or tarred stone of the same | dimensions and thickness is added, rolled and covered with layer of | gravel and quarry chips, also mixed l with tar, one inch in thickness, to be | rolled down from three-fourths to | one-half an inch. A top dressing of | screenings is, then added, and if light | color is desired it may be obtained by | adding a cement. Most of the stone | used here is machine crushed''