.598 INDEX. 



Electrical attraction and repulsion, 524. 

 Electrical balance, 527, PL 40. 

 Electrical light, 340, 518. 

 Electrical machines, 525, PL 40. 

 Electrical pressure, 511. 

 Electric fluid, 508. 

 Electricity, 13, 508, 531, 585. 

 Electricity in equilibrium, 507. 

 Electricity in motion, 516. 

 Electrics, 520. 

 Electrified spheres, PI. 39. 

 Electro-magnetic telegraph, 541. 

 Electro-magnetism, 539. 

 Electrometers, 527, PL 40. 

 Electrophorus, 526, PL 40. 

 Elevation of a projectile, 30. 

 Elevation of liquids, 477, PL 39. 

 Elevations, 438, PL 38. 

 Ellicott, 153. 



Ellipsis, 29, 37, 89, 293, PL 2. 

 Ellipticity of the earth, 435. 

 Elliptic motion of a pendulum, 37- 

 Elliptic orbits, 401. 

 Elliptic vibrations, PL 2. 

 Elongation, 418. 

 Elongation of Venus, PL 34. 

 Elvius, 282. 



Embankments, 237, PL 21. 

 Emery, 149. 

 Emission of light, 341. 

 Empedocles, 374, 582; b. 473, d. 413, B.C. 

 Encaustic paintings, 74. 

 Encroachments of the sea, 563, 564. 

 Encyclopaedia Britannica, 32, 46. 

 Encyclopedic, 192. 

 Energy, 59, 172. 

 Englefield, 490. 

 English foot, 85. 

 English philosophers, 5. 

 Engraving, 71, 91, 188. 

 Engymeter, 82. 

 Epact, 429. 

 Epicureans, 12, 458. 

 Epicurus, 183, 582; b. 342, d. 270, B.C. 

 Epicycles, 455. 



Epicycloidal teeth, 135, PI. 15. 

 Epiglottis, 312. 

 Eprouvette, 103. 

 Equal areas, PL 1. 

 Equalization of force, 148. 

 Equated clocks, 427. 

 Equation of time, 426. 



Equilibrium, 45, PL 3, 8. Stability of equili- 

 brium, 198. 



Equilibrium of animals, 49. 

 Equilibrium of electricity, PL 39. 

 Equilibrium of fluids, PL 19. 

 Equilibrium of gases, 204. 

 Equilibrium of radiant heat, 489. 

 Equinoctial tides, 442. 

 Equinox, PL 34. 

 Eratosthenes, 401, 454. 

 Eridanus, 395. 

 Eskinard, 378. 



Essential properties of matter, 464. 

 Etching, 92. 



Ethereal medium, 362, 472, 482. 

 Euclid, 183, 375. 

 Eudoxus, 182. 

 Euler, 66, 191, 282, 300, 317, 360, 379, 380, 415, 



421, 432, 461, 585. L. Euler, b. 1707, d. 1783. 

 Eumenes, 75. 

 Evaporation, 492, 551. 

 Excitation of electricity, 587- 

 Excitement of heat. 484. 

 Expanse of the universe, 389. 

 Expansion, 491. 

 Expansion of pendulums, 153. 

 Expansion of the air, PI. 24. 

 Expansions, 496. 

 Experiment oh elasticity, 22. 

 Explosions, 560. 

 Extension, 105, 106, 170, 465. 

 Extension of a column, PL 9. 

 Extinction of light, 364. 

 Eyck. Van Eyck, 73, 188; b. 1371, d. 1441. 

 Eye, 350, PL 30. 

 Eyepiece, 336, PL 28. 

 Eytelwein, 285. 



Fabricius, 5/6. 



Fabroni, 587- 



Fahrenheit, 485, 498. 



Falconer, 582. 



Fall in a fluid, 203. 



Fall of a heavy body, 23, 85. 



Fall of a feather, 44. 



Fall of leaves, 571. 



Fan for corn, 264. 



Faraday, 541, 542. 



Fata Morgana, 346. 



Faunius, 276. 



Felt, 143. 



Felting, 143. 



Fermat, 376, 458. 



Fidler, PI. 8. 



Field glass, 336, PL 28. 



Figure of the earth, 435, PL 34. 



Fire, 488. 



Fire engines, 255, 276, PL 23. 



Fishes, 231, 395, 575. 



Fixed ecliptic, 400, PL 32. 



Fixed stars, 387, PL 36, 37. 



Flageolet, 314. 



Flakes of snow, 348. 



Flame, 12. 



Flamsteed, 460, 461 ; b.1646, d.1719- 



Flax, 141. 



Flemish weavers, 187. 



Flexible fibres, 138. 



Flexible vessels, 203. 



Flexure, ]05, 107, 112, 113, 480, 482. 



Flexure of columns and bars, PL [). 

 Floating bodies, 201, 478, PL 19. 



Floodgates, 239, PL 21. 



Floor, 114. 



Flower, 567- 



Fluid, 196. 



Fluids, 195. 



Fluoric acid, 92. 



Fluor spar, 341. 



Flute, 314. 



Flute pipe, PI. 26. 



Fluxions, 191. 



Fly, 101. 



Fly clocks, 145. 



Fly wheels, 137. 



Focus, 324. 



Focus of a lens, 326. 



Focus of the eye, 353. 



Fomalhaut, 395. 



Fondeur, 146. 



Fontenelle, 190, 422. 



Foot, 85. 



Forbes, 505, 506. 



Force, 19, 26, 60. Accelerating force, 21. Cen- 

 trifugal force, 26. Definition of force, 21. 

 Deflective force, 26. Regulation of force, 69. 



Force of electricity, 104. 



Force of magnetism, 104. 



Forces. Regulation of hydraulic forces, 241. 



Forcing pump, 254, 276, PL 23. 



Forge hammer, PL 18. 



Forges, 171. 



Forging, 110. 



Form of the sky, 356. 



Forms of the planets, 412. 

 I Formulae for elasticity of steam, 272. 

 | Forsyth, 571. 



Fossils, 563. 

 I Fourcroy, 588. 

 I Fracture, 105, 110, 113. 



Fracture from heat, 494. 



Frame for rectilinear motion, PL 14. 



Frame saw, PL 4. 



Franc, 96. 



Franklin, 507, 558, 586; b. 1706, d. 1791. 

 Fraunhofer, 343, 505. 

 Frederick II., 145, 457- 

 Freezing, 493, 546. 

 French measures, 85. 



French weights, 96. 



Fresco, 73. 



Friction, 71, 117, 485, 514. Avoiding friction, 



156, 163. 



Friction of fluids, 222, PI. 20, 21. 

 Friction of ice, 501. 

 Friction of scapements, 150. 

 Friction of sluices, 240. 



