11. U.S. patent 34377, February 11, 1862.
12. Davenport & Bridges, car builders of Cambridge, Ma.s.sachusetts, 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 a.r.s.enal, 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.