3876. J 
OEMSON’S upright tubular CORNISH BOILER. 
7 
and the hollow beneath serving as an ash-pit. The fire strikes directly against 
the upper dome-shaped piece, by which the flames are beaten back and forced between 
the tubes, so as to circulate about every portion of the boiler. One of the merits 
claimed for this boiler is that the heat strikes against the dome-like top with 
great force, and is then returned, instead of rushing away up the chimney. It 
seems scarcely possible to make better use of the direct heat drawn from the fuel, 
while it has the power of heating—for heat, that is, caloric, as it gets further and 
further from its source, diminishes in force, and soon loses the power of heating 
other bodies. To test this, let the hand bo held near a good fire, and it would 
soon become scorched, but draw it away, and it is surprising how quickly the heat 
is moderated, and at how short a distance the hand can be held without incon¬ 
venience. Therefore we may conclude that close to its source—the burning fuel 
—the heating action is powerful and prompt, but comparatively little effect is 
produced at a distance from that source. 
Another recommendation of this boiler is its apparent safety and durability. 
Most of the disasters which happen to boilers are due to the deposit of sediment 
at the bottom, and which either causes the metal to burn through, or to expand 
unequally, and so to crack. The facilities for cleansing this boiler are perfect; 
the impurities, necessarily on account of its position, must sink to the bottom; 
from the upper dome they must pass down the tubes to the lower inverted dome, 
