STREET FORMATION

Dominion, Volume 9, Issue 2741, 8 April 1916, Page 12

STREET FORMATION

SOME INTERESTING'' EXPERT-

MENTS.

A marked improvement has lately been made to'the surface of Mercer Street, a thoroughfare which badly ndeded some attention as one tf the main approaches to the Town Hall. In order to determine which was the better of two methods, an experiment was conducted as between the methods of laying down .a tar and bitumen .surface, 60 one side of the roadwas first tarred and then given a coating of a special bitumen supplied by the Vacuum Oil Company, and on the other side thb bitumen was laid down first 011 the macadam,'aud-tar was applied a& a surface. Some little difficulty was experienced in. spreading the bitumen, which had to be laid when very hot, otherwise it thickened and did not spread very easily. The net results, however, are that Mercer Street has now a very gocd 6urface, instead of being .a crrrugatcd road. It is understood that the better results have been obtained hy spreading the tar first, as it takes more kindly'°to the macadam than does the bitumen. Judging by the fact that the plain t^r-spraying. method of giving a street a smooth surface has long been discontinued, it was apparently not a success. In "Upper "Willis Si feet the City Engineer has been trying another method of road formation which b"e believes may' give good results, and be a resistant to the' motor traffic, , which grows heavier in_ Wellington every day. This consists of'a solid foundation of concrete, surfaced with a couple of inches of fine asphalt. The concrete base will, Mr. Morten considers, pievent "waving," which is tlio defect in all street surfaces without a solid, level foundation.