f five miles per hour.
Vivian was associated with Trevethick in the patent.
It was high-pressure, non-condensing, and exhausted into the chimney.
It may be considered the first locomotive to run on rails or trams.
Blenkinsop's locomotive, in 1811, gave still better satisfaction to its owners, and it was usefully employed at the Middleton Colliery in hauling coals on a tramway, the engine having spur-wheels working into a rack on one side of the track.
The engine (A, Fig. 2984) was otherwiregular use. It drew trains of 30 tons weight 3 3/4 miles per hour.
In 1812, Blackett made a series of experiments which proved that the expedient of a pinion and rack-rail was unnecessary; and Chapman patented a
A, Blenkinsop's locomotive (1811). B, Hedley's locomotive (1813）> locomotive with eight wheels driven by gearing, for the purpose of increasing the tractive adhesion.
In the same year, Brunton invented a means of driving a locomotive by two propellers consisting of jointed rods