Hudson and Mohawk Rail Road. 147 
of several hundred pounds to the inch, although it is intended to work 
at a pressure of fifty pounds only. 
There are two cylinders, one on each side of the engine, towards 
the rear of the boiler, each of five inches and a half diameter, and 
sixteen inches stroke. ‘The pistons move on the inside of the wheels, 
which is an improvement on some of the English engines. The 
* shackle bars are connected with the axle of the front wheels, which 
is bent into the shape of a double crank. There is a safety valve on 
the top, of the usual description. 
The power of the engine is over ten horses, and its weight is six 
thousand seven hundred and fifty eight pounds and a half, being 
much less in proportion than that of the best English engines. As it 
stands on the rails, it can be very easily moved by a single hand! 
The tender is a carriage mounted on smaller wheels, and carries a 
square box with an awning upon it, in which are apartments to hold 
an iron tank, and the requisite quantity of fuel. It is dragged next to 
the locomotive, and has’a stout spring in front to keep it at the same 
distance relatively from the engine. Behind these come the coaches 
for the passengers, ‘These run on iron wheels constructed like the 
test, with a flange or inner edge, which makes it impossible for them 
‘0 run off the rails, 
The coaches are built like the common post coaches, peculiar to 
our Own country, and will carry inside and out, about twenty passen- 
gers each, They are very comfortable and convenient, but others 
of the English pattern, are in contemplation. 
‘The following difficulties occurred upon experimenting with this 
gine, The surging of the water in the boiler was so great, that it 
Passed Over into the cylinders. This was remedied by building a 
high steam chamber upon the top of the boiler. ‘The eduction pipes 
is terminated too low in the chimney, and injured the draft, and the 
2 chimney itself was too large. All this was remedied. The anthra- 
Bn Coal was found to pack, and required a blast. An artificial blast 
Was given, and then the heat seemed too great in one place, and too 
®in others. It did not diffuse itself, but melted the grates, and 
the nozzle of the pipe from the wind reservoir. At present it con- 
s!mes wood ; the experiments are not complete, in relation to fuel. 
he average speed of this engine with three loaded cars, equal to 
about eight tons, is fifteen miles an hour, but it has frequently accom- 
Plished with the same load, thirty miles an hour. The writer of this 
“Onumunication, has travelled with it at that rate. 
