4A 4 OUR COMMON ROADS—MURPHY. 
prevent the stones from loosening and being displaced by the 
action of wagon wheels and horses’ feet. * * * The rolling 
was persisted in, with the roller adjusted to different weights up 
to the maximum load” (12 tons) “until it was apparent that the 
opposite effect from that intended was being produced. The 
stones became rounded by the excessive attrition they were sub- 
jected to, their more regular parts wearing away, and the weaker 
and more smaller ones being crushed. ‘The experiment was not 
pushed beyond this point. It was shown that broken stone of 
the ordinary sizes and of the best quality for wear and durability 
would not consolidate in the effectual manner required for the 
surface of a road while entirely isolated from, and independent 
of, other substances.” 
Shell Roads.—Along the Atlantic and Gulf coasts of the United 
States, stone suitable for road-making does not in many districts 
exist. Oyster shells are used, and when applied upon sandy soil, 
it is said, form an excellent road for pleasure driving or light 
traffic, and when properly maintained possess most of the essen- 
tials of a good road. 
Charcoal Roads.—A good road is said to have been made 
through a swampy forest in Michigan in the following manner: 
“ Timber from 6 to 18 inches through was cut 24 feet long, and 
piled up lengthwise in the centre of the road, about five feet high, 
being nine feet wide at the bottom and two at the top, and then 
covered with straw and earth in the manner of coal pits. The 
earth required to cover the pile taken from either side leaves 
two good-sized ditches, and the timber, though not split, is easily 
charred ; and when charred the earth is removed to the side of 
the ditches, the coal raked down to a width of 15 feet, leaving 
it two feet thick at the centre and one at the sides, and the road 
is completed.” Its cost was $600 per mile, and contracts for two 
such roads were given out in Wisconsin at $499 and $500 per 
mile respectively. (Gillespie on roads) 
Such, then, is the history, evolution and practice of road- 
making around us. Let us see if we carry on such a combina- 
tion of facts as present themselves, reason and reflect and adapt 
ourselves to the best methods for the construction and mainten- 
