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

By Benjamin Franklin

Page 84

walk abroad, and are at
the same time heated by the exercise, which double heat is apt to
bring on putrid dangerous fevers? That soldiers and seamen, who must
march and labour in the sun, should in the East or West Indies have
an uniform of white? That summer hats, for men or women, should be
white, as repelling that heat which gives head-achs to many, and to
some the fatal stroke that the French call the _coup de soleil?_ That
the ladies summer hats, however, should be lined with black, as not
reverberating on their faces those rays which are reflected upwards
from the earth or water? That the putting a white cap of paper or
linen _within_ the crown of a black hat, as some do, will not keep
out the heat, though it would if placed _without_. That fruit-walls
being blacked may receive so much heat from the sun in the day-time,
as to continue warm in some degree through the night, and thereby
preserve the fruit from frosts, or forward its growth?--with sundry
other particulars of less or greater importance, that will occur from
time to time to attentive minds?--I am,

Yours affectionately,



_On the Vis Inertiæ of Matter._

_Philadelphia, 1748._


According to my promise, I send you _in writing_ my observations on
your book[18]: you will be the better able to consider them; which
I desire you to do at your leisure, and to set me right where I am

I stumble at the threshold of the building, and therefore have not
read farther. The author's _vis inertiæ essential to matter_, upon
which the whole work is founded, I have not been able to comprehend.
And I do not think he demonstrates at all clearly (at least to me he
does not) that there is really _such a property in matter_.

He says, No. 2. "Let a given body or mass of matter be called
_a_, and let any given celerity be called c. That _celerity_
doubled, tripled, &c. or halved, thirded, &c. will be 2 _c_, 3 _c_,
&c. or ½ _c_, â
“ _c_, &c. respectively: also the _body_ doubled,
tripled, or halved, thirded, will be 2 _a_, 3 _a_, or ½ _a_, â
“ _a_,
respectively." Thus far is clear.--But he adds, "Now to move the body
_a_ with the celerity _c_, requires a certain force to be impressed
upon it; and to move it with a celerity as 2 _c_, requires _twice
that force_ to be impressed upon it, &c." Here I suspect some mistake
creeps in

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Text Comparison with The Complete Works in Philosophy, Politics and Morals of the late Dr. Benjamin Franklin, Vol. 1 [of 3]

Page 7
of the atmosphere at different heights.
Page 10
50 19: for ingenuous, read ingenious.
Page 22
I bought the volume, and read it again and again.
Page 35
He procured me a lodging at Mr.
Page 38
My father, though he could not approve Sir William's proposal, was yet pleased that I had obtained so advantageous a recommendation as that of a person of his rank, and that my industry and economy had enabled me to equip myself so handsomely in so short a period.
Page 52
They were surprised to see, by this and many other examples, that the _American Aquatic_, as they used to call me, was stronger than those who drank porter.
Page 66
He was a middle-aged man, of a good natural disposition, strongly attached to his friends, a great lover of poetry, reading every thing that came in his way, and writing tolerably well, ingenious in many little trifles, and of an agreeable conversation.
Page 73
The merchants who imported articles of stationary solicited my custom; others offered to furnish me with books, and my little trade went on prosperously.
Page 87
With this plain manner, and his penetrating and solid judgment, he was able to confound the most eloquent and subtle of his adversaries, to confirm the opinions of his friends, and to make converts of the unprejudiced who had opposed him.
Page 100
This he agreed to perform; the Penn family withdrew their opposition, and tranquillity was thus once more restored to the province.
Page 147
When a great number of clouds from the sea meet a number of clouds raised from the land, the electrical flashes appear to strike in different parts; and as the clouds are jostled and mixed by the winds, or brought near by the electrical attraction, they continue to give and receive flash after flash, till the electrical fire is equally diffused.
Page 152
Page 161
And though I have taken up the pieces of glass between my fingers immediately after this melting, I never could perceive the least warmth.
Page 189
The experiment was this: To take two phials; charge one of them with lightning from the iron rod, and give the other an equal charge by the electric glass globe, through the prime conductor: when charged, to place them on a table within three or four inches of each other, a small cork ball being suspended by a fine silk thread from the cieling, so as it might play between the wires.
Page 211
In the same way, a strongly negative cloud may occasion a neighbouring cloud to draw into itself from others, an additional quantity, and, passing by it, leave it in a positive state.
Page 213
Page 265
I am rather inclined to the first opinion, but doubtful between the two.
Page 278
Your observations upon the electricity of fogs and the air in Ireland, and upon different circumstances of storms, appear to me very curious, and I thank you for them.
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regard to established ones, thought wisdom in a government, iii.