guments of Bissell's
attorneys, that he agreed to grant a United States patent.[9] It was
issued as no. 17913 on August 4, 1857, and reissued October 18, 1864 as
no. 1794. British patent 1273 had been issued earlier (May 5, 1857), and
patents were also secured in France, Belgium, Austria, and Russia.

The Rogers Locomotive Works in 1858 was one of the earliest builders to
apply the improved truck. By 1860 they had fitted many of their engines
with it and were endorsing the device to prospective customers.

In the same year the _American Railway Review_ noted that the truck was
in extensive use, stating:[10]

... the advantages of the arrangement are so obvious and its results
so well established by practice in this country and Europe that a
treatise on its principles will hardly be needed.

It is no longer an experiment; and the earlier it is applied to all
engines, the better the running and repair accounts will look.

The success of Bissell's invention prompted others to perfect safety
trucks for locomotives. Alba F. Smith came forward in 1862 with the
simple substitution of swing links (fig. 4) for the incline planes.[11]
A swing-bolster truck had been developed 20 years earlier for use on
railroad cars,[12] and while Smith recognized this in his patent, he
based his claim on the specific application of the idea to locomotive
trucks. That the swing links succeeded the incline planes as a centering
device was mainly because they were cheaper and simpler to construct,
and not, as has been claimed, that the V's wore out quickly.[13]

[Illustration: FIGURE 7.--Bissell's 2-wheel truck of 1858 as shown by the
drawing for British patent 2751, issued December 1, 1858.]

Smith's swing-bolster truck, with the heart pendant link, a later
refinement, became the dominating form of centering devices and was used
well into this century. It was to be superseded in more recent years by
the constant resistance and gear roller centering devices which, like
Bissell's invention, depended on the double incline plane principle.

The British-born engineer William S. Hudson, superintendent of the
Rogers Works and an early proponent of the Bissell truck, in 1864
obtained a patent[14] for improving Bissell's safety truck. Hudson
contended that since the Bissell arrangement had a fixed pivot point it
could traverse only one given radius accurately. He proposed to replace
the fixed pivot with a radius bar (see fig. 5)