The boiler pressure is 140 lb., and the tractive force per lb.
The tractive force per pound of mean cylinder pressure is 88.4 lb.
The tractive force was, of course, the Eskimo dogs, and sledges were the means of transportation.
If H could be increased without limit, so also could the tractive force.
He saw himself suddenly the moving hero of the stagery, the tractive force of the situation.