| Page. |
| LIFE of Dr. FRANKLIN | 1 |
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| LETTERS AND PAPERS ON ELECTRICITY. |
| Introductory Letter. | 169 |
| Wonderful effect of points.—Positive and negative electricity.—Electrical kiss.—Counterfeit spider.—Simple and commodious electrical machine. | 170 |
| Observations on the Leyden bottle, with experiments proving the different electrical state of its different surfaces. | 179 |
| Further experiments confirming the preceding observations.—Leyden bottle analysed.—Electrical battery.—Magical Picture.—Electrical wheel or jack.—Electrical feast. | 187 |
| Observations and suppositions, towards forming a new hypothesis, for explaining the several phenomena of thunder-gusts. | 203 |
| Introductory letter to some additional papers. | 216 |
| 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. | 217 |
| Additional experiments: proving that the Leyden bottle has no more electrical fire in it when charged, than before: nor less when discharged: 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. | 245 |
| 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. | 247 |
| Unlimited nature of the electric force. | 250 |
| 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. | 252 |
| Mistake, that 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 cancers. | 256 |
| 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. | 261 |
| Probable cause of the different attractions and repulsions of the two electrified globes mentioned in the two preceding letters. | 264 |
| Reasons for supposing, that the glass globe charges positively, and the sulphur negatively.—Hint respecting a leather globe for experiments when travelling. | ibid. |
| Electrical kite. | 267 |
| Hypothesis, of the sea being the grand source of lightning, retracted.—Positive, and sometimes negative, electricity of the clouds discovered.—New experiments and conjectures in support of this discovery.—Observations recommended for ascertaining the direction of the electric fluid.—Size of rods for conductors to buildings.—Appearance of a thunder-cloud described. | 269 |
| Additional proofs of the positive and negative state of electricity in the clouds.—New method of ascertaining it. | 284 |
| Electrical experiments, with an attempt to account for their several phenomena, &c. | 286 |
| Experiments made in pursuance of those made by Mr. Canton, dated December 6, 1753; with explanations, by Mr. Benjamin Franklin. | 294 |
| Turkey killed by electricity.—Effect of a shock on the operator in making the experiment. | 299 |
| Differences in the qualities of glass.—Account of Domien, an electrician and traveller.—Conjectures 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. | 301 |
| 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. | 309 |
| Notice of another packet of letters. | 313 |
| Extract of a letter from a gentleman in Boston, to Benjamin Franklin, Esq. concerning the crooked direction, and the source of lightning, and the swiftness of the electric fire. | 314 |
| Observations on the subjects of the preceding letter.—Reasons for supposing the sea to be the grand source of lightning.—Reasons for doubting this hypothesis.—Improvement in a globe for raising the electric fire. | 320 |
| Effect of lightning on captain Waddel's compass, and the Dutch church at New York. | 324 |
| Proposal of an experiment to measure the time taken up by an Electric spark, in moving through any given space. | 327 |
| Experiments on boiling water, and glass heated by boiling water.—Doctrine of repulsion in electrised bodies doubted.—Electricity of the atmosphere at different heights.—Electrical horse-race.—Electrical thermometer.—In what cases the electrical fire produces heat.—Wire lengthened by electricity.—Good effect of a rod on the house of Mr. West, of Philadelphia. | 331 |
| 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. | 343 |
| Accounts from Carolina (mentioned in the foregoing letter) of the effects of lightning on two of the rods commonly affixed to houses there, for securing them against lightning. | 361 |
| Mr. William Maine's account of the effects of the lightning on his rod, dated at Indian Land, in South Carolina, Aug. 28, 1760. | 362 |
| On the electricity of the tourmalin. | 369 |
| New observation relating to electricity in the atmosphere. | 373 |
| Flash of lightning that struck St. Bride's steeple. | 374 |
| Best method of securing a powder magazine from lightning. | 375 |
| Of lightning, and the methods (now used in America) of securing buildings and persons from its mischievous effects. | 377 |
| St. Bride's steeple.—Utility of electrical conductors to Steeples.—Singular kind of glass tube. | 382 |
| Experiments, observations, and facts, tending to support the opinion of the utility of long pointed rods, for securing buildings from damage by strokes of lightning. | 383 |
| On the utility of electrical conductors. | 400 |
| On the effects of electricity in paralytic cases. | 401 |
| Electrical experiments on amber. | 403 |
| On the electricity of the fogs in Ireland. | 405 |
| Mode of ascertaining, whether the power, giving a shock to those who touch either the Surinam eel, or the torpedo, be electrical. | 408 |
| On the analogy between magnetism and electricity. | 410 |
| Concerning the mode of rendering meat tender by electricity. | 413 |
| Answer to some queries concerning the choice of glass for the Leyden experiment. | 416 |
| Concerning the Leyden bottle. | 418 |
| APPENDIX. |
| No. 1. Account of experiments made in electricity at Marly. | 420 |
| A more particular account of the same, &c. | 422 |
| Letter of Mr. W. Watson, F. R. S. to the Royal Society, concerning the electrical experiments in England upon thunder-clouds. | 427 |
| No. 2. Remarks on the AbbÉ Nollet's Letters to Benjamin Franklin, Esq. of Philadelphia, on electricity. | 430 |
