MACADAM, GRAVEL, AND EARTH ROADS 1 57 



the road to avoid so much shoveling. 4th. All disposition to 

 load with the finer material because it shoveled easier was 

 eliminated. 5th. Tiie average time at the bin in loading was 

 five minutes when no pressure was applied. If in a hurry, a 

 team would gfo out in two minutes. On the contrary, a driver 

 would take ordinarily at least thirty minutes to load up alone 

 by hand, and would average twenty minutes when extra 

 shovelers were furnished. 6th. Three men, one for running 

 the machinery and two for shoveling, would keep six teams 

 running on a haul of 1 3^ miles from the bank, increasing the 

 number of trips by at least two, the average size of load by 

 one third, and the quality of the product by a large per cent., 

 if the screen were adapted to the work in hand. 



In short, without multiplying figures, the results showed 

 that, speaking conservatively, graveling can be done on a 

 considerably larger scale by the aid of hoisting and screening 

 machinery, without extra expense, and the product will be 

 very much improved. We advise our larger country towns 

 to investigate the subject further, and see if there is not some- 

 thing in the suggestion adapted to their needs. 



MACADAM, GRAVEL, AND EARTH ROADS 



So much is being written and spoken about macadam, 

 gravel, and earth roads, without adequate explanation of the 

 distinctions between them and of their several advantages 

 and disadvantages, that a few words on the subject are in- 

 serted here for general enlightenment. No distinction will 

 be made in this connection between the Macadam and Tel- 

 ford systems. 



A macadam road is one surfaced with crushed stone, put 

 on in layers, the coarser usually at the bottom, and each layer 

 rolled separately. The depth varies with the nature of the 

 traffic and of the foundation, and with the special ideas of the 

 engineer in charge. In all cases the object should be to 

 obtain a sufficient body in the lower layers to hold up tiie 

 traffic out of the softer material beneath at all seasons, and to 

 furnish a surface layer which should be reasonably durable, 

 be hard and smooth while it lasts, and capable of being 

 replaced when worn without serious disturbance to the foun- 

 dation. 



