582 



INDEX. 



Echo, 545. 



Ellipse , equation relative 



to focus, 18. 

 Ellipsoid of elasticity, 451. 



of gyration, 233. 



inverse, 233. 



Jacobi's, 470. 



Maclaurin's, 469. 



moment of inertia 

 of, 241. 



rolling, in Poinsot- 

 motion, 259. 

 potential of, 415. 



at internal 

 point, 418. 



differentiation, 

 419. 



of revolution, poten- 

 tial of, 421. 



Ellipsoidal coordinates, 234, 

 335. 



as equipotential 

 family, 412. 



Elliptic function, 45. 



integral, 45, 47. 

 Ellipticity, 407. 

 Elongation and compres- 

 sion quadric, 441. 



Energy, 65. 



conservation of, 68. 



equation of, 67. 



of distributions, 425. 

 in terms of field, 426. 



emitted by sound- 

 source, 548. 



function for isotro- 

 pic bodies, 457. 



invariant, 457. 

 integral of, in top, 

 277. 



kinetic, 66. 



general form of, 

 112. 



maximum or mini- 

 mum for equilibri- 

 um, 69. 

 potential, 68. 



exhaustion of,76. 



all due to mo- 

 tion, 182. 



of normal vibrations, 

 164. 



relative kinetic, 92. 



of vortex, 515. 



Eolotropic body, 457. 

 Epicycloid, on polhode, 270. 

 Epitrochoids described by 



heavy top, 293. 

 Equation of activity, 66. 



in hydrodyna- 

 mics, 501. 



in generalized 

 coordinates, 125. 



of continuity, 498. 



differential, of mo- 

 tion, 24. 



of forced vibra- 

 tions, 152. 



of equilibrium for de- 

 formable body, 448. 



of hydrodynamics by 

 Hamilton's principle, 

 500. 



Euler's, for rotation, 

 261. 



Laplace's, 349. 



of motion from Ha- 

 milton's principle, 

 114. 



from least ac- 

 tion, 106. 



Lagrange's first 

 form. 



second 

 form, 115. 



Hamilton's ca- 

 nonical, 128. 



Poisson's. 



applied to earth, 

 361. 



for two dimen- 

 sions, 387. 



Equilibrium, 25. 



conditions for, 61,69. 



stable and unstable, 

 69. 



convective, 466. 



equations of for de- 

 formable body, 448. 



theory, 155. 



of tides, 535. 

 Equipollent loads, 486. 

 Equipotential surfaces, 354. 



condition for fa- 

 mily of, 410. 



layers, 372. 



surface of strain, 446 . 

 Erg, 56. 



Erg, unit of energy, 70. 

 Ether, luminiferous , 65. 

 Euler, 73, 173, 499. 



equations of hydro- 

 dynamics, 499. 



angles of, 274. 



dynamical equations 

 of, 260. 



kinematical equa- 

 tions of, 275. 



theorem of 114, 127. 

 Everett, 29, 33. 

 Existence -theorem, 378. 

 Experiment, comparison 



with theory, 51, 52. 

 Expansion -ratio, 434. 



Falling body affected by 

 earth's motion, 323. 



Faraday, 363. 



Field, energy in terms of, 

 426. 



strength of, 353. 

 Fixed point, motion about 



252. 



Fleuriais, 296. ,, 

 Flexion, 489. 

 Flexure, uniform, 490. 



non- uniform, 494. 

 Floating body, equilibrium 



of, 471. 



Flow around corner, 528. 

 Fluid, perfect, 458. 



rotating, 467. 



gravitating rotating, 

 468. 



Flux of vector, 349. 

 Flux -function, 516. 

 Focus, kinetic, 105. 



of plane in null- 

 system, 212. 



Formula, Green's, 370. 



for logarithmic 

 potential, 388. 



Force, definition of, 24. 



accelerational, 120. 



central, 38. 



centrifugal, 119. 



in rigid body, 

 228. 



component, genera- 

 lized, 114. 



effective, 64. 



