has never left the rail and previous to her having this truck she was off the rail almost daily.”²¹ In [p129] the same report Feger stated that he planned to re-equip another locomotive in the same manner.

Figure 11.—The New Jersey Railroad and Transportation Company No. 36, built by the Rogers Locomotive and Machine Works in 1863, was one of the first locomotives to be equipped by this firm with a 2-wheel Bissell truck. (Smithsonian photo 46806-m)

The Baldwin Locomotive Works in December 1860 built a group of rather awkward looking 2-6-0’s for the Louisville and Nashville Railroad. Equipped with Bissell trucks, these were undoubtedly among the very first new locomotives to be so built. The first consolidation type was built by Baldwin in 1866; it was equipped with a 2-wheel Bissell safety truck.

The Rogers Locomotive and Machine Works and the New Jersey Locomotive and Machine Works, both of Paterson, New Jersey, in the early 1860’s began building Moguls; these are known to have had Bissell trucks. Other builders followed their example, so that by the 1870’s 2-wheel trucks had become relatively common.

It should be noted that the 2-wheel truck was not an absolute success until it was equalized with the front driving axle. This arrangement was perfected in 1864 by William S. Hudson, but before describing his invention it will be helpful to discuss several earlier attempts to equalize pony trucks with the drivers.

In 1857 John P. Laird, then master mechanic of the Marietta and Cincinnati Railroad, rebuilt an old Niles 8-wheeler into a curious 2-6-0 on which only the two rear driving wheels were coupled. The front driver was driven by a chain and sprocket, and the pilot wheels were equalized with the front driving axle. The success or failure of the arrangement has not been definitely determined, but whatever the outcome, Laird continued his experiments when he became superintendent of motive power for the Pennsylvania Railroad in 1862. He abandoned the chain drive for a more conventional arrangement of side rods, but the truck and his plan of equalization were much the same as that tried earlier. Laird used two equalizing levers, attached at one end to the front spring hangers and at the other to the truck, [p130] but in a way to allow the truck to swing horizontally. The fulcrum for each lever was mounted on the underside of the front frame rail. A number of old 8-wheel Baldwin flexible-beam engines and several Winans’ Camels were rebuilt in this way. One of these is shown in figure 8. Laird, however, eventually became dissatisfied with his arrangement and re-equipped the engines with Bissell trucks.

John L. Whetstone on April 10, 1860, obtained U.S. patent 27850, which strikingly anticipated the plan Hudson was to develop four years later.²² Whetstone did not use a Bissell truck and was in fact more concerned in relieving the excess weight, often a 50% overload, from the front axle of 0-6-0 locomotives and in distributing a portion of that weight to a pony truck. His arrangement may be readily understood from the patent drawing in figure 9. Probably the best features of the design was the transverse H-beam that connected the spring hangers to the truck frame, which in this case also served as the equalizing lever (note that the ball “C” acts as the fulcrum).

Hudson made use of this same device but in a more practical manner. He found that while the Bissell pony truck could satisfactorily adjust itself laterally and could lead the locomotive around curves, it could not handle the varying loads imposed upon it by the rough trackage typical of American railroads. At one moment an undue amount of weight would fall upon the truck because the drivers were over a depression in the roadbed. This condition overloaded the truck’s springs and also resulted in a momentary loss of adhesion, causing the drivers to slip. Conversely, when the truck hit a depression too much weight was thrust upon the driving wheels, and broken springs or other damage might result.

Hudson’s ingenious remedy to this problem was simple and straightforward (see fig. 10). A heavy equalizing lever that connected the truck to the springs of the front driving wheels was placed on the longitudinal centerline of the locomotive, with the fulcrum under the cylinder saddle. Thus the truck and front driver reacted together to all the inequalities and shocks offered by the roadbed.

[p131]
In October of 1863, under Hudson’s direction, two 2-6-0’s equipped with Bissell trucks were built at the Rogers Works for the New Jersey Railroad and Transportation Company. Probably some fault was found with the suspension of these machines, numbered 35 and 36, for the next 2-6-0, numbered 39, built for the New Jersey road was equipped with Hudson’s equalizer. This engine, completed in January 1865, is believed to be the first Mogul so equipped.