and on Miscellaneous Inventions at the Birmingham Show. 285 
of the compression-piston C, the air is transferred from the 
compression-cylinder A, through the regenerator H, and into 
the heater I', without appreciable change of volume. The result 
is a great increase of pressure, corresponding to the increase of 
temperature, and this impels the power-piston up to the end of 
its stroke. The pressure still remaining in the power-cylinder, 
and re-acting on the compression-piston C, forces the latter 
upward till it reaches nearly to the top of its stroke, when, 
by the cooling of the charge of air, the pressure falls to its 
minimum, the power-piston descends, and the compression 
again begins. In the mean time the heated air in passing 
through the regenerator has left the greater portion of its heat in 
the regenerator-plates, to be picked up and utilised on the return 
of the air towards the heater. 
In the pumping-engines the whole of the water pumped is 
passed directly from the pump through the cooler, thus effectually 
and instantaneously cooling the heated air, which passes down 
the interior of the cooler on its way to the bottom. A very 
small pump is also furnished with the power-engines, which is 
attached like the large pump of the pumping-engine to the side 
of the cooler, and a small stream of water is injected with each 
stroke of the piston. This may be returned, if desired, to the 
barrel or reservoir from whence it is taken, until the water 
becomes in time too warm for effective use ; or it may be 
allowed to run to waste, which is preferable where water is not 
too scarce, as the cooler the compression-cylinder is kept the 
better. Where a pressure of water can be obtained, the small 
pump may be disconnected if desirable, and a very small stream 
allowed to flow into the cooler and pass out at the opposite 
side. 
For pumping a water-supply to farm-buildings, or for a gen- 
tleman's residence, and for innumerable purposes where only a 
small motive-power, say not exceeding two horses, is required, the 
caloric engine appears to be well adapted ; being economical, safe, 
set to work with the least expenditure of fuel and in the shortest 
time, easily managed, needing little attention, and of compara- 
tively low first cost. 
A silver medal was also awarded to Messrs. Marshall, Sons, 
<Sc Co. (Limited), of Gainsborough, Lincolnshire, for their band- 
cutter attached to the self-feeder of a threshing-machine. 
In the section (Fig. 10) g is the revolving barrel of the self- 
feeder placed over the mouth of the drum, the barrel operating 
in conjunction with adjustable oscillating prongs, h, above it. 
A sheet-iron hood, i, is mounted on hinges over the feeding 
apparatus, and is held up by spiral springs in the position 
shown by the dotted lines. A person falling toward the feeder 
