BITUMEN AND PUMICE.

Waipawa Mail, Volume XLIX, Issue 77, 14 March 1928, Page 4

BITUMEN AND PUMICE.

EXPERIMENT ON TAUPO ROADS.

A new- method of treating pumice roads is being tried out hv the Main Highways Board near Taupo. This consists in treating the pumice with a light asphaltic oil, the resultant surface after traffic has ironed it out being practically a bituminous pavement. How the surface will wear has, of course, vet to he determined, hut Mr A. Tyndall, engineer to the Main Highways Board, who has just returned from supervising the work, states that the experiment looks distinctly promising. A section of roadway about 1000 feet long has been treated, the work occupying three days. The section is situated about two miles out from the Terraces Hotel on the Taupo-Napier road. The method adopted was to tear up the road surface and then to spray it with an asphaltic road oil of about the same consistency as thin tar, nine-tenths of a gallon to the square yard being applied. The loose sprayed surface is then thoroughly mixed up by running disc harrows over it. Next comes another spraying of road oil, the same quantity being used as before. Another discing follows, and then a power grader is used to work the mixed material in Windrows to the side of the road. Finally the grader spreads the now thoroughly mixed pumice and oil in a layer about 2 inches thick over Ihe road, and it is left for traffic to iron out. When first laid this surface is of a brown color, but as traffic runs over it it presents a black appearance, and is compacted into a bituminous pavement about 14 inches thick. Mr Tyndall states that a

lorry laden with rails, representing a gross weight of 7 tons, ran over the section just treated and only compressed the surface a quarter of an inch.

The work is on the same lines as tried out last year on sand and sandclay roads in California and New Mexico. If the experiment is a success it may revolutionise road conditions in the pumice areas in the interior of the North Island. Stone for road-making is scarce in these Darts, but if a durable surface can be created by the application of road oil direct to the pumice itself, it will be possible to have good, hardsurfaced highways right through the pumice country at a comparatively small expense. HUMOR A’WHEEL. Nothing works out right. In n town where you can park as long as vou want to there is no reason why you should want to. “The percentage of accidents due to drivers being asleep at the wheel greatly increased last year,” says the “Wichita Eagle.” “Motors are now fool-proof, hut the fool must be awake. ’ ’ NO EFFECT! “You tell me,” said the Magistrate, “that this is the person who knocked you down with his motor car. Can you swear to him?” “I did,” returned the complainant eagerly, “but he only swore back at me and drove on.”