BROAD OR NARROW TIRES.

New Zealand Mail, 30 December 1892, Page 5

BROAD OR NARROW TIRES.

An American authority on farming has been giving his opinion on the question of narrow v. broad tires for farm waggons, in the New York Times. He says, in referring to the belief that narrow tires are easier of draught than broad ones, this wholly baseless belief is due to the common ignorance of the laws of dynamics, which govern the practice of moving vehicles on roads. But some of these laws are so simple that a child cannot be mistaken when the principles are explained. Everyone knows that a waggon going up a hill requires more force to draw it than when it is moved on a level. Now, when a wheel sinks in soft soil there is an elevation in the ground in front of it equal to the depth of the sinking. When a narrow wheel sinks three or four inches in the ground, the effect is precisely the same as if "the waggon was going up the same incline, and when the broad wheel is used and it does not sink in the ground this obstacle does not exist. The surface of a wheel does not interfere in the least with the draught of a waggon, even on solid hard ground, and it must be evident that the broad wheel will not cut into a road as a narrow one will, and thus on soft roads it must be of easier draught. He concludes his observations with the following remarlc3 :—' If a complete account of the cost of the narrow tires in the shape of lost time, greater expense of maintaining the roads, washing of the fields by the ruts cut in the land, the extra labour of horses, and all other evil results of this amazing blunder were figured up, the amount would provide new waggons with broad tires for every farmer in the country, and would leave a comfortable surplus to remain in the farmer's pockets.