Hocking Valley class M-1

Shortly after the C&O had gained control over the Hocking Valley Railway, they ordered new Mikados for them which were similar to their own class K-1. ALCO-Richmond delivered numbers 180 to 184 in 1912, followed by 185 to 190 in 1913. They had oversquare cylinders with a diameter of 29 inches and a stroke of only 28 inches. At 56 inches, the driver diameter was one inch smaller than that of the C&O locomotives. The boiler was originally pressed to 170 psi, what was later increased to 185 psi. 

When the Hocking Valley was completely incorporated into the C&O in 1930, these locomotives became class K No. 1089 to 1099. Some documents even counted them as class K-1, as they had many similarities with the original class K-1.