Induction 44-47, 175-194, 277, 287,
202 sq., 275, 277, 288, 334, 335; cal-
culation of 338

Instantaneous spreading of electricity
307, 319-323, 326
Insulation 100

Iron, conductivity of 398, 576, 687, note
32

J.

Jar 223; capacity of jars 573, 581

K.

Kinnersley (Ebenezer, Physician in Phil-
adelphia, b. 1712) 126, 136, 213; see
new experiments of electricity, Phil.
Trans. 1763, 1773

Knob for discharging 511, 572

L.

Lac 371, 374, 376, 518, 520

Lac solution 494

Lane, Timothy, F.R.S. (b. 1734, d. 1804)
136, 213, 601

Lane's electrometer 263, 329, 540, 544,

559, 569, 570, 571, 580

Law of electric force from Exp. I. 291,
note 19

Leakage, electric 260, 264, 393-
Leather 608

Leyden vial 128, 206, 313, 363, 389
Light, Newton's fits 354

Light round the edge of coating 307,

326, 532; brightest at first charging,
310

Limetree wood 588, 611

Linen thread 244

Lines of discharge of torpedo 400
Link 602

Loops of chain 433, 605

M.

Machine for trying coated plates 295,
337, 340, 366, 495; new for measuring
thickness 517

Machine, electric 242

Magazine of electricity 207, 521, 563
Mahogany 590

Matter 4

Maximum density of electric fluid 20
and note 1

Measurements of apparatus 219, 255,

273, 275, 466, 472
Mechanism for Exp. I. 222
Mercury 366

Metals, conducting power 397, 398
Method of trying charges 241, note 17
Method of the work 2

Michell (Rev. John, F.R.S., d. 1793) 354
Mineral water warehouse 415
Moist wood 392

Moment, statical 388

Moveable electricity in glass 350
Moveable fluid 12, 350

N.

Nairne, Edward, F.R.S., d. 1806; Mr N.
601; plates from 482 (315); jar 568;
electric machine 559, 568; his own
large one 580; his manner of lacquer-
ing 496; his batteries 585, 616
Needle discharger 572
Negative electrification 463
Newton 18, 19, 97

Newton's fits 354

N. O. P. Q. 459, 462, 592
Nuremberg glass 301, 376, 497

0.

Oblong, charge of 284, 479; coatings
320

Oil of vitriol 626, 694
Overcharge 6

P.

p-ratio of charge spread uniformly on
disk to that collected in circumference
140; estimated value by experiment
276, 281, 289

p ratio of circumference of circle to
diameter 594

Penetration of electric fluid into glass
132, 169-174, 332, 339, 349, 355, 363
Pensylvania, Phil. Soc. of 437
Pith ball electrometer 220, 240, 244,
358, 359

Plate air 134, 340; concave 155; circu-
lar 55-65, 140; thin 73

Plates, coated, lists of 315, 324, 325,
370; theory of 129; two circular 74,
82, 141-144

Points, discharge of electricity by 123
Positive electrification 100, 101; defined
to be that of glass 217; gives same
proportion of charges as negative 364
Potential 199 (note)

Priestley (Joseph, F.R.S., LL.D. Edin.,
b. 1733, d. 1804) 125, 126, 213, 354,
408, 601

Prime conductor 241, 295, 359, 539
Prop. IX. 292

XVIII. 269

XIX. 140

XXII. cor. 5, 140

XXIV. 144, 150

XXIX. 282

XXX. 289

XXXI. 285

XXXIV. 311

Xxxv. 351.

XXXVI. 365

Pulleys 295

Q.

Quad. nitre 626, 696

R. 584, 591, 603

Rain water 524

Real charge 313

Real fluid 91, 94

R.

Reciprocity of induction 334
Reduced charge 270, 272
Redundant fluid 13
Reel 636, 644

Repulsion 106; of balls as square of

redundant fluid 386, 525, 563
Repulsion, effect of too great 49
Resistance, electric, varies as length of
conductor 131; what power of ve-
locity 574, 575, 629, 686; effect of
heat on 619, 620, 690

Richard 511, 565
Ronayne, Thomas 601

Rosin 336, 371, 461, 464, 488

Rosin varnish 497; experimental 514,

520, 548; plates 518, 555, 560, 594
Roughness dissipates electricity 387
Rows of battery 581

Rules for trial plates 592; for strength

tried by 637, 645

Spark, electric 135-139, 212; none from
torpedo 401; length does not depend
on number of jars 402, 604, note 10
Specific gravity of salt water 587, 588
Specific inductive capacity 332, 339,
notes 15, 27

Spherical shell 18, 19
Spirit of salt, 627, 694
Spirit of wine 524, 631

Spreading of electricity 299-367, 484,
485, 512; gradual 494-500
Springing wire 296

Square, charge of 282, 283, 479 and note

22; plates of various substances 269
Steam, cause of explosion by lightning
137

Stool, electric 420, 612

Strata, conducting, in glass 351, 354
Strength of electrification 355; effect on

capacity 356, 451, 463, 539

System of coated plates 316

Specific gravity 595

Solutions of salt, &c. 689, 694, 695,
696

Trial plates 465

Tubes 575, 632, 633, 636
Thermometer tube 383, 562
Thickness of plates, effect on charge
269, 272; of coated plates 314; of air
plates 341; measurement 517, 594,
595

Three parallel plates 288
Tinfoil 222; discharger 426
Torpedo, 1st wooden 409, 415, 596; 2nd
leather 416, 600, 608, 611, 612, 615;
in basket 421; in sand 422; in net
424. See note 29

Touching, to compare charges 413, 441,
582, 583

Trial plate, theory of 153 and note 17;
list of 590; description of 238, 239,
296, 297, 298, 454, 457, 465, 592;
charge as square root of surface 247,
251, 284; sliding wire 447; sliding
cylinder 547, 567

Trough, torpedo 410, 587

Tubes, measures of 632-635

Undercharge 6

U.

W.

Wainscot 561, 590, 609

Walsh (John, F.R. S., M. P., d. 1795) 395,

396, 401, 415, 421, 424, 430
Wasting of electricity 393, 394, 486, 487
Water, resistance of 398; distilled 617,

621, 688; rain 617; purged of air
624, 692; impregnated with fixed air
625, 693; pump 684; sea 524, 684
Wax 387

Waxed glass 255, 271, 295, 447, 450, 476,
541, 563

Weather, effect of on coated plates 304
Weight of electric fluid 5
White glass 301, 460

Wilcke (Johann Karl, b. 1732, d. 1796)
134

Williamson, Hugh, M.D. 437
Wilson (Benjamin, F.R.S., b. 1721, d.
1788) 125

Wind, electric 125

Wire 219, 240; charge of 279, 479, 683;

trials of 447, 448; connecting, allow
ance for 337; in straw electrometer
387, 388

Wires compared with canals of incom

pressible fluid 94, 278 and note 3
"Work," MS. so called 349