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

By Benjamin Franklin

Page 261

sound
did not seem faint, as if at a distance, like distant sounds through
air, but smart and strong, and as if present just at the ear.--I wish
you would repeat these experiments now you are upon the subject, and
add your own observations.--And if you were to repeat, with your
naturally exact attention and observation, the common experiment of
the bell in the exhausted receiver, possibly something new may occur
to you, in considering,

1. Whether the experiment is not ambiguous; _i. e._ whether the
gradual exhausting of the air, as it creates an increasing difference
of pressure on the outside, may not occasion in the glass a
difficulty of vibrating, that renders it less fit to communicate to
the air without, the vibrations that strike it from within; and the
diminution of the sound arise from this cause, rather than from the
diminution of the air?

2. Whether, as the particles of air themselves are at a distance
from each other, there must not be some medium between them, proper
for conveying sound, since otherwise it would stop at the first
particle?

3. Whether the great difference we experience in hearing sounds at
a distance, when the wind blows towards us from the sonorous body,
or towards that from us, can be well accounted for by adding to or
subtracting from the swiftness of sound, the degree of swiftness that
is in the wind at the time? The latter is so small in proportion,
that it seems as if it could scarce produce any sensible effect,
and yet the difference is very great. Does not this give some hint,
as if there might be a subtle fluid, the conductor of sound, which
moves at different times in different directions over the surface of
the earth, and whose motion may perhaps be much swifter than that of
the air in our strongest winds; and that in passing through air, it
may communicate that motion to the air which we call wind, though a
motion in no degree so swift as its own?

4. It is somewhere related, that a pistol fired on the top of an
exceeding high mountain, made a noise like thunder in the valleys
below. Perhaps this fact is not exactly related: but if it is, would
not one imagine from it, that the rarer the air, the greater sound
might be produced in it from the same cause?

5. Those balls of fire which are sometimes seen passing over a
country, computed by philosophers to be often thirty miles high at
least, sometimes burst at that height; the air must be exceeding rare
there, and

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Text Comparison with Memoirs of Benjamin Franklin; Written by Himself. [Vol. 2 of 2] With his Most Interesting Essays, Letters, and Miscellaneous Writings; Familiar, Moral, Political, Economical, and Philosophical, Selected with Care from All His Published Productions, and Comprising Whatever Is Most Entertaining and Valuable to the General Reader

Page 6
139 To Mr.
Page 30
Neither is this science only useful to the merchant, but is reckoned the _primum mobile_ (or first mover) of all mundane affairs in general, and is useful for all sorts and degrees of men, from the highest to the lowest.
Page 31
By its help engineers conduct all their works, take the situation and plan of towns, forts, and castles, measure their distances from one another, and carry their measures into places that are only accessible to the eye.
Page 42
Yet I ought to have charity for these unhappy people, when I consider that, with all this wisdom of which I am boasting, there are certain things in the world so tempting, for example, the apples of King John, which, happily, are not to be bought; for if they were put to sale by auction, I might very easily be led to ruin myself in the purchase, and find that I had once more given too much for the _whistle_.
Page 44
The vast quantity.
Page 65
, a high-spirited monarch! every light expression which happened to displease him was construed by his supple judges into a libel, and sometimes extended to high treason.
Page 70
In looking over one of the volumes of this work a few days ago, I found a little piece written by one of our countrymen, and which our vigilant neighbours had taken from the London Chronicle in 1766.
Page 74
The attentive husband may judge by certain prognostics when the storm is nigh at hand.
Page 76
dreadful summoners grace!" This ceremony completed and the house thoroughly evacuated, the next operation is to smear the walls and ceilings of every room and closet with brushes dipped in a solution of lime, called _white wash_; to pour buckets of water over every floor, and scratch all the partitions and wainscots with rough brushes wet with soapsuds and dipped in stonecutter's sand.
Page 82
"La cause de tous les relachemens vient de l'impunite des crimes, et non de la moderation des peines.
Page 99
, _to be perfectly honest_).
Page 108
Here is a waste of land that might afford subsistence for so many of the human species.
Page 117
There was among the twelve apostles one traitor, who betrayed with a kiss.
Page 139
I requested from the Congress last year my discharge from this public station, that I might enjoy a little leisure.
Page 151
It would be one of the noblest amusements.
Page 156
" * * * * * "_David Hartley.
Page 165
, which was once made, was from a circumstance scarce unavoidable.
Page 203
Small black clouds thus appearing in a clear sky, in hot climates portend storms, and warn seamen to hand their sails.
Page 210
in the plate_, forming a long and sharp cone.
Page 223
FRANKLIN.