Part 2

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, 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.

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.[23]

The Locomotive Engine Safety Truck Company (see fig. 11) was formed in the 1870's, with A. F. Smith as president, to exploit the patents of Bissell, Smith, and Hudson. For several years notices appeared in the columns of the _Railroad Gazette_ reporting suits by the Company against various railroads and locomotive builders for unauthorized use of their patents. The _Gazette_ of May 29, 1875, carries a protest of the Company against the Manchester Locomotive Works for unlicensed use of Smith's patent of 1862. In the issue of August 28, 1875, is reported the Company's success in establishing the validity of Smith's patent:

Some important settlements for the use of the patent have lately been made with the company, one of them being with the Western Railroad Association, whose headquarters are at Chicago, which includes the principal western roads. Through this the company receives its royalty on several hundred locomotives.

IN SUMMARY

It can be stated that Hudson's modification of the Bissell truck is of unquestioned importance, for without the introduction of the equalizer it is doubtful if the 2-wheel pony truck would have been a complete success on American railroads. Bissell's 4-wheel truck was extensively employed, but it did not enjoy the universal popularity of the 2-wheel truck, and in the 1880's was eclipsed by other forms of 4-wheel safety trucks. The Hudson-Bissell pony truck, however, survived in its basic form to recent times, when, in the late 1940's and early 1950's, the last steam locomotives were constructed in this country.

1. Three-point suspension in a 4-2-0 was easily gained--the center plate of the truck and the two bearings of the driving wheel axle. On a 4-4-0 the center plate served as one point, while the fulcrum of each equalizing lever served as the other two points, thus providing the desirable and highly stable 3-point suspension.

2. _American Railroad Journal_, 1853, vol. 9, p. 427.

3. Connecting both truck axles with an equalizing lever so that they acted in sympathy with each other also did much to prevent derailments on rough trackage.

4. Bissell states in the patent specification that inclined planes had been previously applied to railroad car trucks. His claim rested on the application of this device to locomotive trucks.

5. From a sworn statement of G. M. Milligan dated July 2, 1857. This along with letters, petitions, receipts, and other such material quoted in this discussion are from the Patent Office papers housed in the National Archives, Washington, D.C. (hereafter referred to as Patent Office papers).

6. The _Lebanon_ was a 4-4-0, used in freight service, that had been built by the New Jersey Locomotive and Machine Company in December 1855.

7. Letter dated July 2, 1857, from S. L. Moore (Patent Office papers).

8. Statement cited in footnote 5.

9. Letter dated July 11, 1857, Charles Mason to Levi Bissell (Patent Office papers).

10. _American Railway Review_, February 9, 1860, vol. 2, p. 71.

11. U.S. patent 34377, February 11, 1862.

12. Davenport & Bridges, car builders of Cambridge, Massachusetts, in 1841, obtained a U.S. patent for a swing-beam truck.

13. Gustavus Weissenborn in his authoritative _American Locomotive Engineering and Railway Mechanism_ (New York, 1871, p. 131), stated that when in use the V's soon acquired a polished surface which seemed to defy wear.

14. U.S. patent 42662, May 10, 1864.

15. _Engineering_, July 12, 1867, vol. 4, p. 29.

16. John Headden, master mechanic of the New Jersey Railroad and Transportation Company, built at the road's Jersey City shops several locomotives equipped with Hudson's variety of the Bissell truck. Headden, upon the death of Hudson, succeeded him in 1881 as superintendent of the Roger Works.

17. It is believed that Harrison, Winans and Eastwick made one of the first uses of a 2-wheel radial truck on a 2-6-0 built at the Alexandrovsky Arsenal, St. Petersburg, in 1844-46. The success or exact particulars of these machines is unknown. See John Jahn, _Die Dampflokomotive in Entwicklungsgeschichtlicher Darstellung Ihres Gesamtaufbaues_, Berlin, 1924, p. 239; Richard E. Peunoyer, "Messrs. Harrison, Winans & Eastwick, St. Petersburg, Russia," _Railway and Locomotive Historical Society Bulletin_ no. 47, September 1938, p. 46; and Joseph Harrison, Jr., _The Locomotive Engine, and Philadelphia's Share in its Early Improvements_, Philadelphia, 1872, p. 52.

18. Zerah Colburn, _Locomotive Engineering and the Mechanism of Railways_, ..., London, 1871, p. 99. Zerah Colburn (1832-1870) was one of the best informed and most vocal authorities on 19th-century American locomotive construction. He not only designed advanced machines while working at the New Jersey Locomotive Works but also advocated many reforms in locomotive design. He published the _Railroad Advocate_ in New York City for several years. In 1858 he became editor of _The Engineer_ and in 1866 founded the technical journal _Engineering_.

19. _American Railway Review_, June 8, 1860, vol. 2, p. 392. Holley was a well known authority on locomotive engineering and the author of several books on the subject.

20. _Engineering_ May 11, 1866, vol. 1, p. 313. By this time (1866), the Eastern Counties Railway had become part of the Great Eastern system.

21. _American Railway Review_ July 26, 1860, vol. 2, p. 38.

22. Whetstone was chief designer for Niles & Co., a Cincinnati locomotive builder. His invention apparently did not receive a test, since the company closed shortly before the patent was granted. No other builder seemed interested.

23. Paul T. Warner, "Mogul Type Locomotives," _Railway and Locomotive Historical Society Bulletin_ no. 100, April 1959.

U.S. GOVERNMENT PRINTING OFFICE: 1961

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington 25, D.C.--Price 20 cents