★ Keep up to date with the latest news - subscribe to the Transcribe Bentham newsletter; Find a new page to transcribe in our list of Untranscribed Manuscripts
Click Here To Edit Dec:r 1793 Flash P
In the Steam Engine
the Chamber must
be cast all in one
place viz: of Cast
Iron at the cheapest.
That iron must be
of great strength and
of a strength increasing
in proportion to
the power of the steam
that is in proportion
to the size of the
Chamber
In the Steam Engine
the whole of the water
in the Boiler must
be brought to the Boiling
Heat before any
steam is formed - before
any power is
produced and then
2 There must be a
constant supply of
caloric to make up
for what is carried
off by the containing surrounding
bodies vessel. Then
3. There must be
another supply of
caloric to convert
the water into steam
But the quantity of
caloric absorbed by
a given weight of
water when converted
into steam is much
greater than the
quantity of caloric
absorbed by a given
the same weight of
air when expanded to
twice its bulk.
In the Flash Pump
the Chamber need
not be all of a piece
it may be of thin
lead or copper or it
be well supported
with brick work.
The strength will
only be in proportion
to the quantity of
water in height:
i: if a fluid in
an state.
it will not increase
with the diameter
of the flash-chamber
The Chamber
must certainly be
strong - but this only
at bottom: and
the strength even
be given by arch
work, or by the
ground where circumstances
admitt
of its being built
low enough
Nor need the strength
be for a greater
part of the height
than that to which
the water will be
raised
Suppose 1/2 the
utmost quantity of
the air that can be
driven out and
32 foot the height
to which the water
could rise if the
whole of the air were
driven out: - the
16 foot is the
utmost of the waters
rise by a single flash
flash. To be
if it be deemed advisable
to raise
the water be by successive
flashes before
it is let out then
the strength must
be according sufficient for to a
greater height of
water
Quere which is best?
to work with single
flashes, or successive
flashes?
By a single flash
you get say 16
foot rise of water
By 2 flashes you
get 24 feet of water.
Quere which has
most power? one
cylinder of 24 foot
altitude: or 2 cylinders
of the same
diameter, each of
16 foot altitude.
As the more water
the greater more of
the caloric is wasted
in forming steam
with it, the power
of the Machine
depends absolutely
upon the driness of
the match: therefore
1. There It will be
worth while to make & keep
it dry in the Match-
Chamber or the
Exsiccation place
2. No moist fuel
nothing of oil or turpentine
should be
employ'd.
Air changing Machine
The Winnowing machine
may be made
to move by wind while
there is any - the
machinery requisite
will be very little
The wind alone without
the Windmill
would not do, since
it would neither move
always in the proper
direction, nor fast
enough.
Could any thinguse
be made of the force
acquired by the burnt air
from its expulsion ".
Hardly - since it
would not act. but
in proportion as it was
in a state of compression,
nor would it be
kept in a state of compression,
but at the
expence of the ventilation power.
Tube for the standard
a Steam Engine of the greatest
Diameter say 8 foot.
Find by what quantity
and expence of
Coal a certain quantity
of water can
be raised to a gi
certain height in a
certain time. Compare
this effect
with that of a Flash
Pump: worked suppose
by shavings
or rather by straw
for facility of calculation,
by straw.
The Steam EngineFlash Pump
will give per minute
Strokes only to x
Steam Engine n x
n x =24 or 26
Number of strokes given
in a minute by the
Steam Engine 9
- by Flash Pump 5
Power resulting from the Height to which the water
is raised by a stroke
of the Steam Engine - 4
- by Flash Pump 3
Expence of a stroke
by Steam Engine - x
-by Flash Pump - y
Advantage will be
of Steam Eng. 5h/x
of Flash P.a 3H/y
Price of Straw fewel
compared to Coal fuel
Weight of a Truss
of Straw - lb 36
No of Trusses in
a load 36
—
Weight of a load }
of straw} 1296
Weight of a Ton }
of Coal - - 2240
Price of a Ton of} £-s-d
Coal}
of a Ton of Straw}
Dry Straw has certainly
much more combustible
matter than the purest Coal
Coal containing
1. So much more Earth
2. Its combustible matter
consisting of oil which
by combustion is reduced
to water which water
consumes caloric in
being formed into vapour
Lavoisiers Annales
14 199 Water
Straw contains 7
times as much caloric
as water does.
on heat.
Present Price of Straw
per load 1-10-0
Cheapest ordinary 1-1-0
price
|
Identifier: | JB/106/013/003 "JB/" can not be assigned to a declared number type with value 106.
|
|||
|---|---|---|---|
|
1793-12 |
|||
|
106 |
|||
|
013 |
flash-pump |
||
|
003 |
flash & steam engine |
||
|
text sheet |
2 |
||
|
recto |
|||
|
jeremy bentham |
[[watermarks::[w with crown] [lion motif]]] |
||
|
34601 |
|||