[44] This should be collected and “weathered” so as to get rid of mud and any organic matter in it.
[45] In Paris 3 to 3·75 ton miles of roller are applied to every cubic yard of metal; in America 5 ton miles are thought necessary.
[46] Vide ‘Roads, Streets, and Pavements,’ by Q. A. Gillmore, p. 89.
[47] Vide Aveling and Porter’s pamphlet on ‘Steam Road Rolling,’ p. 32.
[48] Vide Aveling and Porter’s pamphlet on ‘Steam Road Rolling,’ p. 33.
[49] Vide ‘The Use of Steam Rollers,’ by A. W. Parry, Reading.
[50] Some road surveyors contend that for gravelled roads 6-ton rollers are heavy enough, for macadam roads 12-ton rollers.
[51] Traffic in making a roadway is apt to grind off the sharp edges and spoil the metal before it is set.
[52] ‘Report on the Economy of Road Maintenance and Horse Draught through Steam Rolling, with special reference to the Metropolis,’ by Frederick A. Paget, C.E., etc. etc., London 1870, to which I refer my readers for many scientific and useful facts upon this subject.