The Complete Works in Philosophy, Politics and Morals of the late Dr. Benjamin Franklin, Vol. 2 [of 3]

By Benjamin Franklin

Page 181

several very easy experiments. Take any clear
glass bottle (a Florence flask stript of the straw is best) place it
before the fire, and as the air within is warmed and rarefied, part
of it will be driven out of the bottle; turn it up, place its mouth
in a vessel of water, and remove it from the fire; then, as the air
within cools and contracts, you will see the water rise in the neck
of the bottle, supplying the place of just so much air as was driven
out. Hold a large hot coal near the side of the bottle, and as the
air within feels the heat, it will again distend and force out the
water.--Or, fill a bladder not quite full of air, tie the neck tight,
and lay it before a fire as near as may be without scorching the
bladder; as the air within heats, you will perceive it to swell and
fill the bladder, till it becomes tight, as if full blown: remove it
to a cool place, and you will see it fall gradually, till it becomes
as lank as at first.

2. Air rarefied and distended by heat is[44] specifically
lighter than it was before, and will rise in other air of greater
density. As wood, oil, or any other matter specifically lighter than
water, if placed at the bottom of a vessel of water, will rise till
it comes to the top; so rarefied air will rise in common air, till
it either comes to air of equal weight, or is by cold reduced to its
former density.

A fire then being made in any chimney, the air over the fire is
rarefied by the heat, becomes lighter, and therefore immediately
rises in the funnel, and goes out; the other air in the room (flowing
towards the chimney) supplies its place, is rarefied in its turn, and
rises likewise; the place of the air thus carried out of the room,
is supplied by fresh air coming in through doors and windows, or, if
they be shut, through every crevice with violence, as may be seen by
holding a candle to a key-hole: If the room be so tight as that all
the crevices together will not supply so much air as is continually
carried off, then, in a little time, the current up the funnel must
flag, and the smoke being no longer driven up, must come into the
room.

1. Fire (_i. e._ common fire) throws out light, heat, and smoke (or
fume.) The two first move in right lines, and with great swiftness,
the

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Text Comparison with Franklin's Way to Wealth; or, "Poor Richard Improved"

Page 0
and T.
Page 1
half bound 1 0 Wonders of the Horse, recorded in Anecdotes, Prose and Verse, by Joseph Taylor 2 6 Tales of the Robin & other Small Birds, in Verse, by Joseph Taylor 2 6 Instructive Conversation Cards, consisting .
Page 2
The hour of the sale not being come, they were conversing on the badness of the times; and one of the company called to a plain, clean, old man, with white locks, 'Pray, Father Abraham, what think you of the times? Will not those heavy taxes quite ruin the country! How shall we be ever able to pay them? What would you advise us to?'----Father Abraham stood up, and replied, 'If you would have my advice, I will give it you in short; "for a word to the wise is enough," as Poor Richard says.
Page 3
--"But, dost thou love life? then do not squander time, for that is the stuff life is made of," as Poor Richard says.
Page 4
'But with our industry we must likewise be steady, settled, and careful, and oversee our own affairs with our own eyes, and not trust too much to others: for, as Poor Richard says, "I never saw an oft-removed tree, Nor yet an oft-removed family, That throve so well as those that settled be.
Page 5
Octr.
Page 6
" And again, "At a great pennyworth pause a while:" he means, that perhaps the cheapness is apparent only, and not real; or the bargain, by straitening thee in thy business, may do thee more harm than good.
Page 7
" It is, however, a folly soon punished: for, as Poor Richard says, "Pride that dines on vanity, sups on contempt;--Pride breakfasted with Plenty, dined with Poverty and supped with Infamy.
Page 8
" The day comes round before you are aware, and the demand is made before you are prepared to satisfy it; or, if you bear your debt in mind, the term, which at first seemed so long, will, as it lessens, appear extremely short: "Time will seem to have added wings to his heels as well as his shoulders.
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--I am, as ever, thine to serve thee, RICHARD SAUNDERS.