THE UNIVERSITY OF MICHIGAN DEARBORN CAMPUS LIBRARY

E

302.

F f 2

13

THE

WORKS

OF

DR. BENJAMIN FRANKLIN,

IN

PHILOSOPHY, POLITICS, AND MORALS:

CONTAINING, BESIDE ALL THE WRITINGS PUBLISHED
IN FORMER COLLECTIONS, HIS

DIPLOMATIC CORRESPONDENCE,

AS MINISTER OF THE UNITED STATES, AT
THE COURT OF VERSAILLES;

A VARIETY OF LITERARY ARTÍCLES;

AND

EPISTOLARY CORRESPONDENCE,

NEVER BEFORE PUBLISHED.

WITH

MEMOIRS AND ANECDOTES OF HIS LIFE.

VOL. III.

PHILADELPHIA: PRINTED AND PUBLISHED BY WILLIAM DUANE.

CONTENTS.

VOL. III.

LETTERS AND PAPERS ON ELECTRICITY.

INTRODUCTORY Letter. -

Wonderful effects of points-Positive and negative electricity.-
Electrical kiss.-Counterfeit spider.-Simple and commodious elec-
trical machine.

Observations on the Leyden bottle, with experiments proving the dif-

ferent electrical state of its different surfaces.

Further experiments confirming the preceding observations.-Leyden

bottle analysed.-Electrical battery.-Magical picture.-Electrical

wheel or jack.--Electrical feast.

Observations and suppositions, towards forming a new hypothesis, for

explaining the several phenomena of thunder-gusts.

Introductory letter to some additional papers.

Opinions and conjectures, concerning the properties and effects of the

electrical matter, and the means of preserving buildings, ships, &c.

from lightning, arising from experiments and observations made at

Philadelphia, 1749.—Golden fish.-Extraction of effluvial virtues by

electricity impracticable. -

:

Additional experiments: proving that the Leyden bottle has no more

electrical fire in it when charged, than before: nor less when dis-

charged that in discharging, the fire does not issue from the wire

and the coating at the same time, as some have thought, but that

the coating always receives what is discharged by the wire, or an

equal quantity: the outer surface being always in a negative state
of electricity, when the inner surface is in a positive state.

Accumulation of the electrical fire proved to be in the electrified

glass.-Effect of lightning on the needle of compasses, explained.-

Gunpowder fired by the electric flame.

Unlimited nature of the electric force.

The terms, electric per se, and non-electric, improper.-New relation

between Metals and water.-Effects of air in electrical experiments.

-Experiment for discovering more of the qualities of the electric

fluid.

76

Mistake, that the only metals and water were conductors, rectified.—

Supposition of a region of electric fire above our atmosphere.-

Theorem concerning light.-Poke-weed a cure for canceres. 71

New experiments.-Paradoxes inferred from them.-Difference in

the electricity of a globe of glass charged, and a globe of sulphur.-

Difficulty of ascertaining which is positive and which negative.

Probable cause of the different attractions and repulsions of the two

electrified globes mentioned in the two preceding letters.

Reasons for supposing that the glass globe charges positively, and the

sulphur negatively.-Hint respecting a leather globe for experi-

ments when travelling.

78

- ibid.

82

Account of the experiments made at Marly, by the Abbé Mazeas. 81
A more particular account of the experiment before the Academy of
Sciences at Paris, by M. d'Alibard.

Account of the experiments upon thunder clouds by Dr. Watson. 86

Remarks on the Abbé Nollet's letters to Benjamin Franklin, by C.

Colden, of New York.

Effects of oil on water, in a letter to Dr. Pringle.

On stilling the waves by oil, by Dr. Franklin.

Dr. Farish on the same subject.

Dr. Franklin to Dr. Brownrigg on the same subject.

Mr. Tegnagel to Count Bentinck on the same subject.

Electrical kite.

88

97

98

99

- 100

106

- 110

Hypothesis, of the sea being the grand source of lightning, retracted.

Positive, and sometimes negative, electricity of the clouds discover-

ed.-New experiments and conjectures in support of this discove-

ry.-Observations recommended for ascertaining the direction of

the electric fluid.-Size of rods for conductors to buildings.-Ap-

pearance of a thunder-cloud described.

Additional proofs of the positive and negative state of electricity in

the clouds.-New method of ascertaining it.

Electrical experiments, with an attempt to account for their several

phenomena, &c.

Experiments made in pursuance of those made by Mr. Canton, dated

December 6, 1753; with explanations, by Benjamin Franklin. - 130

Turkey killed by electricity.-Effect of a shock on the operator in

making the experiment.

Differences in the qualities of glass.-Account of Domien, an electri-

cian and traveller.-Conjectures respecting the pores of glass.—Ori-

gin of the author's idea of drawing down lightning.—No satisfactory

hypothesis respecting the manner in which clouds become electri-

fied. Six men knocked down at once by an electrical shock.-Re-

flections on the spirit of invention.

134

- 136

Beccaria's work on electricity.-Sentiments of Franklin on pointed

rods, not fully understood in Europe.-Effect of lightning on the

church of Newbury, in New England.-Remarks on the subject. 143