For commuter trains, the Lackawanna needed a passenger locomotive that would combine the ability to burn culm, what means waste from anthracite mining, with the simplest possible maintenance and high tractive effort. It received a Wootten firebox, the grate of which was extraordinarily large in relation to the heating surface and, at 87,7 square feet, was probably one of the largest ever on a 4-4-0. This required a two-part Camelback cab. In order to achieve the required traction, the cylinders were dimensioned sufficiently and at the same time a moderately large driving wheel diameter was selected. The construction of the locomotive itself was kept as simple as possible.
Initially they were classified in the class 19C, but soon received new class designations with “G” for the 4-4-0 wheel arrangement. The first three batches consisted of a total of 27 locomotives and were delivered by ALCO-Schenectady between 1901 and 1903. Although they were almost identical in construction, they received the class designations G-2, G-3 and G-4. All other production lots differed in details and became the G-5 to G-9. Of these, 15 were initially delivered by Baldwin in 1904 before ALCO-Schenectady delivered 12 more in 1905 and finally the last 11 in 1910 and 1911.
Two examples of the class G-6 were equipped with superheaters of Cole type ex works and formed the class G-7. Since the lubrication was not easy to implement with this, this type of superheater was soon removed again. Between 1916 and 1921 many of the locomotives were again fitted with a superheater, but this time a Schmidt type. There were again slight differences in these conversions, which was reflected in the addition of an “a” or “b” after the class names. A single locomotive was given cylinders with a diameter of 21 instead of 20 inches, which earned it the different designation G-10b.
Even the saturated version developed a high power compared to other locomotives with the 4-4-0 wheel arrangement and could haul trains with six cars at an average of 40 mph on the existing mountain lines. Nevertheless, they later had to be used for suburban trains, since their tractive power soon no longer met the increased requirements. Ten locomotives were converted to conventional cabs in the 1920s and thus survived somewhat longer than their non-converted sisters. Most were retired just before World War II.
