Although the first successful internal combustion engine was invented in 1860 by Lenoir, practical applications were not developed until the close of the century. Diesel patented his engine in 1892, and in 1893 both Karl Benz and Henry Ford built their first motorcars.
Practical oil and gasoline burning internal combustion engines permit the recruiting of Armored and Mechanized regiments and the upgrading of older units to these modern types. Additionally, Drillers may improve Oil wells to Level III, producing six units per turn.
