Builder photo of Construction Number 1314 showing right side of 42 inch gauge Southern Lumber and Timber Company 36 Ton Two Truck Heisler Geared Steam Locomotive Number 10 at Erie, Pennsylvania, June 1915. This locomotive was used for logging near Hillsdale, Mississippi. Photograph by Schauble.

Builder photo of Construction Number 1338 showing right side of Solvay Process Company 36 Ton Two Truck Heisler Geared Steam Locomotive Number 44 at Erie, Pennsylvania, April 1916. This locomotive was used for mining near Wyandotte, Michigan. Photograph by Schauble.

Builders photo of left side of Solvay Process Company 50 Ton Two Truck Heisler Geared Steam Locomotive Number 14 at Erie, Pennsylvania, 1930's. This locomotive was used for mining at the Sibley Quarries near Detroit, Michigan. Photograph by Schauble.

Builder photo of Construction Number 1385 or 1386 showing right side of Solvay Process Company 36 Ton, Two Truck Heisler Geared Steam Locomotive Number 10 at Erie, Pennsylvania, February 1919. This is either Construction Number 1385 or 1386 and was used for mining at the Sibley Quarries near Detroit, Michigan. Photograph by Schauble.

Builder photo of Construction Number 1354 showing right side of Snohomish Logging Company 47 Ton Two Truck Heisler Geared Steam Locomotive Number 6 at Erie, Pennsylvania, September 1917. This locomotive was used for logging near Snohomish, Washington. Photograph by Schauble.

Builder photo of Construction Number 1334 showing right side of Snohomish Logging Company 53 Ton Two Truck Heisler Geared Steam Locomotive Number 5 at Erie, Pennsylvania, May 1916. This locomotive was used for logging near Snohomish, Washington. Photograph by Schauble.

Builder photo of Construction Number 1205 showing right side of Smith-McGowin Mill Company 50 Ton Two Truck Heisler Geared Steam Locomotive Number 7 at Erie, Pennsylvania, June 1910. This locomotive was used for logging near Magazine, Alabama. Photograph by Schauble.

Builder photo of Construction Number 1136 showing left side of Smith-McGowin Mill Company 31 Ton Two Truck Heisler Geared Steam Locomotive Number 6 at Erie, Pennsylvania in December 1907. This locomotive was used for logging at Magazine, Alabama. Photograph by Schauble.

Builder photo of Construction Number 1349 showing right side of Smith Powers Logging Company 75 Ton Three Truck Heisler Geared Steam Locomotive Number 8 at Erie, Pennsylvania, October 1916. This locomotive was used for logging near Powers, Oregon. Photograph by Schauble.

Builder photo of Construction Number 1036 showing right front side of California 50 Ton Two Truck Heisler Geared Steam Locomotive Number 9 at Erie, Pennsylvania in December 1899. Some of the early models were built with a water tank over the boiler. Photograph by Schauble.