The life of George Stephenson, railway engineer - Lighthouse ...

134 LIFE OF GEORGE STEPHENSON. [chap. xii.
reaction of which very often caused the fracture of the rails,
and occasionally threw the engine off the road.
To remedy this imperfection, Mr. Stephenson devised a new
chair, with an entirely new mode of fixing the rails therein.
Instead of adopting the hutt joint which had hitherto been used
in all cast-iron rails, he adopted the half-lap joint, by which
means the rails extended a certain distance over each other at
the ends, somewhat like a scarf joint. These ends, instead of
resting upon the flat chair, were made to rest upon the apex of
a curve forming the bottom of the chair. The supports were
extended from three feet to three feet nine inches or four feet
apart. These rails were accordingly substituted for the old cast-
iron plates on the Killingworth Colliery Railway, and they were
found to be a very great improvement upon the previous system,
adding both to the efficiency of the horse power (still used on
the railway) and to the smooth action of the locomotive engine,
but more particularly increasing the efficiency of the latter.
This improved form of the rail and chair was embodied in a
patent taken out in the joint names of Mr. Losh, of Newcastle,
iron-founder, and of Mr. Stephenson, bearing date the 30th of
September, 1816.* Mr. Losh being a wealthy, enterprising
iron-manufacturer, and having confidence in George Stephenson
and his improvements, found the money for the purpose of taking
out the patent, which, in those days, was a very costly as well as
troublesome affair.
The specification of the same patent also described various
important improvements on all locomotives previously con-
structed. The wheels of the engine were improved, being
altered from cast to malleable iron, in whole or in part, by
which they were made lighter as well as more durable and safe.
Thus the road was rendered smoother, and the wheels of the
* A grant unto William Losh, of the town and county of Newcastle-npon-
Ty ne, iron-founder, and George Stephenson, of Killingworth^ in the county of
Northumberland, engineer, for their invented new method or new methods of
facilitating the conveyance of carriages, and all manner of goods and materials
along railways and tramways, by certain inventions and improvements in the
constniotion of the machine, carriages, carriage-wheels, railways, and tramways
employed for that purpose.—30th Sept. 1816. Patent Record Office, Number
4067.