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

By Benjamin Franklin

Page 272

within about an inch, and there
_remain_.


OBSERVATION.

This seems a proof, that though the small sharpened part of the wire
must have had a _less natural_ quantity in it before the operation,
than the thick blunt part; yet a greater quantity was _driven down
from it_ to the balls. Thence it is again inferred, that the pointed
rod is rendered _more negative_: and farther, that if a _stroke must
fall_ from the cloud over a building, furnished with such a rod,
it is more likely to be drawn to that pointed rod, than to a blunt
one; as being more strongly negative, and of course its attraction
stronger. And it seems more eligible, that the lightning should fall
on the point of the conductor (provided to convey it into the earth)
than on any other part of the building, _thence_ to proceed to such
conductor. Which end is also more likely to be obtained by the length
and loftiness of the rod; as protecting more extensively the building
under it.

It has been _objected_, that erecting pointed rods upon _edifices_,
is to _invite_ and draw the lightning into _them_; and therefore
dangerous. Were such rods to be erected on buildings, _without
continuing the communication_ quite down into the moist earth, this
objection might then have weight; but when such compleat conductors
are made, the lightning is invited not into the building, but into
the _earth_, the situation it aims at, and which it always seizes
every help to obtain, even from broken partial metalline conductors.

It has also been suggested, that from such electric experiments
_nothing certain can be concluded as to the great operations of
nature_; since it is often seen, that experiments, which have
succeeded in small, in large have failed. It is true that in
mechanics this has sometimes happened. But when it is considered
that we owe our first knowledge of the nature and operations of
lightning, to observations on such small experiments; and that on
carefully comparing the most accurate accounts of former facts, and
the exactest relations of those that have occurred since, the effects
have surprizingly agreed with the theory; it is humbly conceived that
in natural philosophy, in this branch of it at least, the suggestion
has not so much weight; and that the farther new experiments now
adduced in recommendation of _long_ sharp-pointed rods, may have some
claim to credit and consideration.

It has been urged too, that though points may have considerable
effects on a _small_ prime conductor at _small distances_; yet on
_great_ clouds and at _great distances_, nothing is to be expected
from them. To this it is answered,

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Text Comparison with Benjamin Franklin and the First Balloons

Page 0
The recent bi-centenary of Franklin's birth, which coincided with the revival of interest in balloons, makes this a timely topic, especially since Franklin's descriptions of the first balloon ascensions are almost unknown and do not appear among his philosophical papers.
Page 1
Care was taken before the Hour to replace what Portion had been lost, of the inflammable Air, or of its Force, by injecting more.
Page 2
A Note secur'd from the Weather had been affix'd to the Globe, signifying the Time & Place of its Departure, and praying those who might happen to find it, to send an account of its State to certain Persons at Paris.
Page 3
One has ordered four of 15 feet Diameter each; I know not with what Purpose; But such is the present Enthusiasm for promoting and improving this Discovery, that probably we shall soon make considerable Progress in the art of constructing and using the Machines.
Page 4
The Basket contained a sheep, a duck, and a Cock, who, except the Cock, received no hurt by the fall.
Page 5
But as more perfect Accounts of the Construction and Management of that Machine have been and will be published before your Transactions, and from which Extracts may be made that will be more particular and therefore more satisfactory, I think it best not to print those Letters.
Page 6
The Persons who were plac'd in the Gallery made of Wicker, and attached to the Outside near the Bottom, had each of them a Port thro' which they could pass Sheaves of Straw into the Grate to keep up the Flame, & thereby keep the Balloon full.
Page 7
conveying Intelligence into, or out of a besieged Town, giving Signals to distant Places, or the like.
Page 8
It may be attended with important Consequences that no one can foresee.
Page 9
BANKS, Bar^t.
Page 10
Means were used, I am told, to prevent the great Balloon's rising so high as might indanger its Bursting.
Page 11
Sir JOSEPH BANKS, Bar^t.
Page 12
In paragraph three, for "Post," in Smyth, read "Port;" in paragraph six for "Adventures," in Smyth, read "Adventurers;" in paragraph thirteen.
Page 13
The plate forming the frontispiece to this volume shows the balloon as seen from Mr.
Page 14
14, "Carr" corrected to "Car" in "on both Sides their Car,"; p.