1. Might not the mineral used for by Dr Lewis
for his portable furnaces under the name of
black lead be employ'd in this way to advantage?
2. Could not means be found of detaining the
air in the oven till it had attained the
heat desired? for instance by a loaded valve
or a pair of loaded valves, one for discharging,
the other for receiving. In proportion to the heat of
the air is its elasticity: in proportion to its elasticity is its power of lifting up the valve.
3. The discharging valve ought to be must be placed at the exit
of the oven: if it be within the oven itself
it will be difficult if not impracticable to
get at it, either to observe the state of it when
at work, or to repair it.
4. The exit of the oven or discharging place
ought to be at the spot where it ceases to
acquire any fresh heat. The channel should
not be lengthened so as to be carried beyond
that point, unless it be necessary for the sake
of giving it direction: i:e: to prevent its
being carried finding its way to certain some portion of space to
which it would find its way otherwise. For
the longer the channel, the more of the heat will
be wasted in warming the channel absorbed by and wasted upon it.
Identifier: | JB/119/051/001
"JB/" can not be assigned to a declared number type with value 119.
note to p. 6 warming
note to p. 6
d1 e1 / e2 / d3 e3 / d4
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