Abbildungen der Seite

of Domien, an Electrician and Traveller. — Con-

jectures respecting the Pores of Glass. — Origin of

the Author's Idea of drawing down Lightning. —

No satisfactory Hypothesis respecting the Manner

in which Clouds become electrified. — Six Men

knocked down at once by an Electrical Shock. —

Reflections on the Spirit of Invention . • . 347

To M. Dalibard. 29 June, 1755.

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 355

To John Pringle. 21 December, 1757.

On the Effects of Electricity in Paralytic Cases . 359

To Thomas Hubbard. 28 April, 1758.

Electrical Apparatus.— Description of a Battery . 361

To William Heberden. 7 June, 1759.

On the Electricity of the Tourmalin . . . 363

E. Kinnersley To B. Franklin. 12 March, 1761.

Experiments on boiling Water, and Glass heated by

boiling Water. — Doctrine of Repulsion in elec-

trized Bodies doubted. —Electricity of the Atmo-

sphere at different Heights. — Electrical Horse-

race.— Electrical Thermometer.—In what Cases

the Electrical Fire produces Heat — Wire length-

ened by Electricity. — Good Effect of a Rod on

the House of Mr. West, of Philadelphia , . .367

To E. Kinnersley. 20 February, 1762.

Answer to some of the foregoing Subjects.— How

long the Leyden Bottle may be kept charged.—

Heated Glass rendered permeable by the Electric

Fluid. — Electrical Attraction and Repulsion.—

Reply to other Subjects in the preceding Paper. —

Numerous Ways of kindling Fire.—Explosion of

Water. — Knobs and Points 378

Accounts from Carolina (mentioned in the foregoing

Letter) of the Effects of Lightning on two of the

Rods commonly affixed to Houses there, for secur-

ing them against Lightning. 1 November, 1760 . 395

Mr. William Maine's Account of the Effects of the

Lightning on his Rod, dated at Indian Land, in

South Carolina, August 28th, 1760 . . . .396

Remarks by Benjamin Franklin 398

To Miss Mary Stevenson. 22 March, 1762.

Concerning the Leyden Bottle 403

Electrical Experiments on Amber. 3 July, 1762 . . 403

John Winthrop To B. Franklin. 29 Sept, 1762.

New Observation relating to Electricity in the At-

mosphere 405

Alexander Shall To B. Franklin.

Flash of Lightning that struck St Bride's Steeple 406

To Peter Franklin.

Best Method of securing a Powder Magazine from

Lightning 407

To Thomas Ronatne. 20 April, 1766.

On the Electricity of the Fogs in Ireland . . 409

Mode of ascertaining whether the Power, giving a Shock

to those who touch either the Surinam Eel or the

Torpedo, be Electrical 412

Addition, 12 August, 1772, in Consequence of the Ex-

periments and Discoveries made in France by Mr.

Walsh, and communicated by him to Dr. Franklin 413

Of Lightning, and the Methods (now used in America)

of securing Buildings and Persons from its mis-

chievous Effects. September, 1767 . . . 414

John Winthrop To B. Franklin. 6 January, 1768.

St Bride's Steeple 419

To John Winthrop. 2 July, 1768.

On Conductors for protecting Houses from Light-

ning. — Singular Kind of Glass Tube . . .419

E. Kinnerslet To B. Franklin. 13 October, 1770.

On some Electrical Experiments made with Char-

coal 426
To Major Dawson, Engineer. 29 May, 1772.

« ZurückWeiter »