THE ANGLE OF TRACTION, ETC. 245 



a carriage gives the horses as much work to do as two 

 men placed in front. 



Now we have just seen that the lever power of any 

 two wheels in overcoming obstacles — and, except on a 

 railway, there are always obstacles to overcome — is pro- 

 portionate to their height or diameter ; but in most 

 carriages the fore wheels are made of considerably less 

 height than the hind ones for the convenience of turn- 

 ing, the room required being thereby considerably 

 lessened, therefore it is proposed to load the weaker 

 pair of wheels more heavily than the stronger ones. 

 In point of fact, however, the matter would be still 

 worse than this, for the fore wheels, whatever their 

 relative height may be, have always heavier work to do 

 than the hinder ones, for whom they crush obstacles 

 and open smooth tracks — planing the way, as it were, for 

 them. It is, however, altogether unnecessary to go 

 into theory here, as we have abundance of practical 

 experience that this notion is altogether incorrect. In 

 the older systems of Artillery — Gribeauval's for instance, 

 which had 46-inch fore and 62-inch hind wheels — it 

 was considered impracticable to put more than one-half 

 the load on the front axle that the hinder one carried. 

 When, however, the Englisli Artillery, at the beginning 

 of this century, determined on carrying a much greater 

 quantity of ammunition on the limber than had been 

 hitherto done, the fore wheels were made of the same 

 height as the hind ones ; but even then, with the old 

 smooth-bore guns, the front wheels were not loaded 

 equally with the hind ones.* It is therefore a mistake 



* One of the defects of the modern systems is, that they disar- 

 range the entire balance of the guns and limbers, the gun itself 

 being lighter and the ammunition heavier. In this respect the 

 reverse of progress has been made. 



