268 



Journal of Agriculture. 



[8 May, 1908. 



CLEARING BY TRACTION ENGINE. 



.4. S. Kenyoii, C.E., Engineer for Agriculture. 



One of the difficulties met with in the use oi the traction engine on-' 

 the farm is the inability of the' ground to supply sufficient resistance tO'- 

 the driving wheels to prevent them skidding. This is particularly the case 

 after rains, in wet ground, and in sand. It is, of course, evident that the 

 pull of the ploughs, trees, or whatever is being hauled by the encrine, 

 must not be greater than the frictional resistance between the ground, 

 and the wheel. Many expedients have been devised to overcome the diffi- 

 culty. The traction engine has been evolved under " old country " condi- 

 tions for use on good and hard roads, and fails at times when taken into- 

 the field. Grips, spikes, widening, and increasing the diameter of the 

 wheels have all been tried. In the Western States of America, traction 

 engines with wheels up to 16 feet in width of face are in use, while others 

 have an arrangement similar to the horse tread-mill whereby they run 

 on a continuous roadbed. In general, it mav be said that the best method; 

 lies in the direction of wider wheels, though strength of axle considera- 

 tions puts a practical limit to this. 



IkAi llt.iX I.NGINK WlLil I )kl .A I dNOUGil'J' ATTACIIMKM . 



An interesting problem of this kind arose in South Australia, and a- 

 satisfactory solution has been found by the adoption of a modification of 

 an old contrivance known under various names, but more commonlv 

 as the pedo-rail. At Tintinara there occur large tracts of gum country, 

 interspersed with the smaller grass tree, .sedge, and black gum. The soil 

 is white sand overlying clay, with occasional heavy limestone outcrops. 

 Belts of mallee mingled with heathy vegetation show here and there. 

 Large areas of true heath country, honeysuckle, oak, and scrub, are to be- 



