120 REPORT—1849. 
It is seen, by the model at present working, that we effect our object by using 
gravitation, as a medium for ob- 
taining the power of the steam. 
Weights A and B are raised 
twice every revolution, through 
a space equal to the stroke ; and 
in falling, give back the force 
which raised them but little di- 
minished. D is a counterpoise 
to the cylinder N, and the parts 
connected with it. The cylin- 
der, piston and rod, steam- 
chest V, &c., are like those of 
the ordinary engine ; the whole 
revolves on standards, one of 
which is seen at Q, bolted on 
a bed-plate T. The axle turns 
in brasses, which are in the upper part of the standards, and are quite independent 
of the valves, placed on the extremities of the axle, for the purpose of admitting the 
steam or carrying off the waste: these valves work against metallic plates, into 
which are screwed respectively the steam and waste pipes, and which are bolted 
to, and adjustable on shelves cast upon the standards. The weights are attached to 
the cross-head of the piston-rod, which, as well as eyes fixed to the other extremi- 
ties of the weights, slide upon the guide-rods Fand F. So little power is wasted 
by this engine, that we found 823 to represent the effective force, the whole power 
of the steam being considered as 84. The action of the steam is precisely in the 
required direction, at whatever part of the revolution the weights may be raised. 
The plan we have endeavoured to carry out has, no doubt, occurred to many 
persons long since; but we have reason, from our own experiments, to conclude that 
it was most probably abandoned, whenever tried, on account of difficulties which 
would scarcely have been anticipated, at least to their full extent ; and which would 
have discouraged us, were we not determined to persevere, as long as any prospect 
of success should remain. To overcome these difficulties cost us more than three 
years of labour and the expenditure of several hundred pounds.—One of the chief 
of them was the stopping, with sufficient gentleness, those masses of matter con- 
tained in the weights. The moving parts of the ordinary engine are gradually set 
in motion or brought to rest, chiefly by means of the crank; and whatever con- 
sumption of steam or loss of power occurs, is nearly, if not entirely, concealed from 
the ordinary observer. But, in our case, if the reciprocating parts were not, with 
gentleness and certainty, brought into a state of rest, the engine would be greatly 
injured, or destroyed. The weights, which are thrown up with very considerable 
velocity, cannot be stopped by solid or unyielding matter, since it would cause the 
most injurious concussions. On the small scale, springs might be used for the pur- 
pose, although any person who makes the experiment will find, that while they prevent 
concussion they cause a very objectionable amount of vibration: on the large scale, 
they would be quite inadmissible. But, as is perceived by the model now working, 
so gently are the weights moved and stopped by the means we employ, that not 
the slightest noise, concussion, or vibration is produced. And I pledge myself that 
increasing the size does not diminish these advantages. I work almost every day, 
and often for many hours a day, aa engine which, among others, I constructed myself 
upon this principle. Its weight amounts to about 160 lbs., and it makes ordinarily 
120 revolutions per minute, that is, 160 lbs. are stopped and put in motion 240 
times per minute; and yet this produces no more noise nor vibration than is per- 
ceived with the smallest model. It is so free from any kind of strain, that I 
habitually work it at its highest velocity, while merely resting on its bearings—there 
being nothing whatever pressing down on the axle to keep it in its place. My friend 
Mr. John J. Allingham has now nearly finished an engine which may be worked 
up to eight-horse power, and I am perfectly satisfied that it will revolve with the 
same gentleness and silence. : 
It might at first be supposed, that we should require large and clumsy weights :— 


