OUR COMMON ROADS—MURPHY. 44:7 
7 tons, and the engine which draws it must be capable of remov- 
ing it from one place to another. The cost of the broken mate- 
rial will be approximately, where boulders are available, without 
the expense of quarrying,— 
Collecting, sledging and supplying to machine...... $0 35 
Bren mcime by TaG ies os <iesecc yore <ccsnclers aig guere 0 eer ere's 0 30 
Carting- from depotitoroad . 2.62.6... - ce qoe senses 0 20 
Wear and tear of machinery, removing machine, 
BGHEENIG MOCEF Races dei el afal Ss SMe Rt oe es Yate ci dL toate s C 05 
eTItOm Of broken StONe. 662 3's sieheve ols Se side ole. $0 90 
Owing to the large quantities of whin stone, iron stone, trap 
and other metamorphic and igneous rock available with quarry- 
ing in Nova Scotia, it may be possible to get the broken material 
for the price given above. Ninety cents per ton will, however, 
be considered a minimum price by parties who have used the stone- 
breaking machine now in common use. 
From these data we may be able to estimate what a mile of 
road would cost treated according to the system of McAdam, but 
with proper drainage to suit our climate. 
M. Ducreux, M. Gasparin, and Mr. Leahy give about 55 per 
cent, as the amount of solid stone contained in broken stone 
metalling of 2 to 24 inch diameter or gauge, the other 45 per 
cent, being void. A simple proportion will show that in this 
case a ton of stone will produce rather less than ; of a cubic yard. 
Now if we assume our typical road to be well drained, properly 
formed, eight feet of the centre to be coated with 6 inches in 
thickness of McAdam, the remainder, or wings, to make 21 feet, 
to be of clay or gravel, a blinding of 1 or 14 inches of the fine 
material (run through the screens at the crusher), to be spread 
over the broken stones and the whole consolidated by a roller, 
we may approximately estimate the cost of a mile thus: 
9 
