Experiments and Observations on Electricity Made at Philadelphia in America

Transcriber's note: Text enclosed by underscores is in italics (_italics_).
In view of the difficulty of reliably distinguishing 18th-century variant
spellings from typographical errors, the text has been reproduced entirely
as printed.

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EXPERIMENTS

AND

OBSERVATIONS

ON

ELECTRICITY,

MADE AT

_Philadelphia_ in _America_,

BY

Mr. BENJAMIN FRANKLIN,

AND

Communicated in several Letters to Mr. P. COLLINSON,
of _London_, F. R. S.

*       *       *       *       *       *

_LONDON_:

Printed and sold by E. CAVE, at _St. John's Gate_. 1751.
(_Price 2s. 6d._)




The PREFACE.


_It may be necessary to acquaint the reader, that the following
observations and experiments were not drawn up with a view to their being
made publick, but were communicated at different times, and most of them in
letters wrote on various topicks, as matters only of private amusement._

_But some persons to whom they were read, and who had themselves been
conversant in electrical disquisitions, were of opinion, they contain'd so
many curious and interesting particulars relative to this affair, that it
would be doing a kind of injustice to the publick, to confine them solely
to the limits of a private acquaintance._

_The Editor was therefore prevailed upon to commit such extracts of
letters, and other detach'd pieces as were in his hands to the press,
without waiting for the ingenious author's permission so to do; and this
was done with the less hesitation, as it was apprehended the author's
engagements in other affairs, would scarce afford him leisure to give the
publick his reflections and experiments on the subject, finish'd with that
care and precision, of which the treatise before us shews he is alike
studious and capable. He was only apprized of the step that had been thus
taken, while the first sheets were in the press, and time enough for him to
transmit some farther remarks, together with a few corrections and
additions, which are placed at the end, and may be consulted in the
perusal._

_The experiments which our author relates are most of them peculiar to
himself; they are conducted with judgment, and the inferences from them
plain and conclusive; though sometimes proposed under the terms of
suppositions and conjectures._

_And indeed the scene he opens, strikes us with a pleasing astonishment,
whilst he conducts us by a train of facts and judicious reflections, to a
probable cause of those phænomena, which are at once the most awful, and,
hitherto, accounted for with the least verisimilitude._

_He exhibits to our consideration, an invisible, subtile matter,
disseminated through all nature in various proportions, equally unobserved,
and, whilst all those bodies to which it peculiarly adheres are alike
charged with it, inoffensive._

_He shews, however, that if an unequal distribution is by any means brought
about; if there is a coacervation in one part of space, a less proportion,
vacuity, or want, in another; by the near approach of a body capable of
conducting the coacervated part to the emptier space, it becomes perhaps
the most formidable and irresistible agent in the universe. Animals are in
an Instant struck breathless, bodies almost impervious by any force yet
known, are perforated, and metals fused by it, in a moment._

_From the similar effects of lightening and electricity our author has been
led to make some propable conjectures on the cause of the former; and at
the same time, to propose some rational experiments in order to secure
ourselves, and those things on which its force is often directed, from its
pernicious effects; a circumstance of no small importance to the publick,
and therefore worthy of the utmost attention._

_It has, indeed, been of late the fashion to ascribe every grand or unusual
operation of nature, such as lightening and earthquakes, to electricity;
not, as one would imagine, from the manner of reasoning on these occasions,
that the authors of these schemes have, discovered any connection betwixt
the cause and effect, or saw in what manner they were related; but, as it
would seem, merely because they were unacquainted with any other agent, of
which it could not positively be said the connection was impossible._

_But of these, and many other interesting circumstances, the reader will be
more satisfactorily informed in the following letters, to which he is
therefore referred by_

_The_ EDITOR.




[Illustration]




LETTER I.

FROM

Mr BENJ. FRANKLIN, in _Philadelphia_.

TO

Mr PETER COLLINSON, F.R.S. _London_.

_July 28, 1747_.

  _SIR_,

THE necessary trouble of copying long letters, which perhaps when they come
to your hands may contain nothing new, or worth your reading (so quick is
the progress made with you in Electricity) half discourages me from writing
any more on that subject. Yet I cannot forbear adding a few observations on
M.