GENERAL INDEX. 41 



Page 



Thermometer, Crieh ton's metallic ones . . . . HEAT * . .19 



Howard's ... 19 



Murray's proposed scale .... . . .18 



various experiments with . .... ... 18 



Tide-wheel described HYDRAULICS . . 23 



Tides, cause of, described ....... PRELIMINARY TREAT. 16 



Tints, chromatic Vernier for subdividing .... POLAR. OF LIGHT . 52 



.. polarised, their deviation from those of Newton's scale . . 32 



. . of the rings in hypo-sulphate of lime .... . 35 



Vesuvian, or Idocrase .... 35 



Topaz, splendour of its coloured rings . . . . : . 23 



virtual poles of its rings .... . . 33 



Torricellian vacuum, experiments on . . . . . HEAT . . 2 



Toucan or egg-eater, its curious bill ..... PRELIMINARY TREAT . 32 



Trammel, an instrument for drawing ellipses .... . 7 



Transmission of pressure of fluids PNEUMATICS . . 5 



of sounds . 29 



Transparency of bodies, cause of ..... OPTICS . . .60 



Triple crank, description of ...... HYDRAULICS . 12 



Trundles of the lantern wheel ...... JMECHANICS, t. ii. . 30 



Truths, mathematical and physical distinguished . . . PRELIMINARY TREAT. 7 



-Vacuo, boiling of water in, account of .... HEAT , . 51 



distillation of gases, vinegar and water in . . . . . .58 



freezing of water in ...... ... 53 



Vacuum, Torricellian ....... ... 2 



Vanilla, peculiarity of the growth of that plant . . . PRELIMINARY TREAT. 27 



Vaporization, cause of it explained ..... HEAT . . .58 



Vapours, definition of. as distinguished from gases . . PNEUMATICS . 2 



.. table of the latent heat in ..... HEAT . . .48 



the elastic force of, and of steam . . ... 48 



Vegetables, effects of light on ..... PREL. TREAT. 27. OPTICS 64 



impregnation of, remarks on . . . . PRELIMINARY TREAT. 27 



Velocity of de>cent by gravity equal in all bodies ... MECHANICS, t. i. . 10 



its effects on friction ...... t. iii. . 30 



of light calculated ...... PREL. TREAT. 17. OPTICS 2 



Velocity of falling bodies, accelerated in their descent . . PRELIMINARY TREAT. 10 



.. of radiant heat computed ..... HEAT . . 23 



of a stream or river, methods of calculating . . HYDRAUL. 5. MECH. t. i. 22 



proper for water-wheels gene/ally .... HYDRAULICS . 27 



an overshot wheel ..... MECHANICS,!. 5. . 21 



of water in pipes, calculated .... HYDRAULICS . 5 



virtual, principle of ...... MECHANICS, t. ii. . 2 



Vera's rope-pump described . . . . . HYDRAULICS . 9 



Vernier, chromatic, description of ..... POLAR. OF LIGHT . 52 



Vesuvian, tints in its rings ...... . 35 



Vince's experiments on friction ...... MECHANICS, t. iii. . 7 9 



Vince and Colomb compared as experimenters .... . 11 



Vinegar, distillation of, in vacuo ..... HEAT . . 58 



Virginia creeper, peculiarity in the tendrils of that plant . . PRELIMINARY TREAT. 27 

 Virtual velocities, principle of, and applications . . MECHANICS, t. ii. 2, 22, 28, 42 



Virtual poles of the rings of Tppaz ..... POLAR. OF LIGHT . 33 



Visible objects, duration of ...... OPTICS . . 42 



Vision, causes of its being erect ..... . . .42 



distinct and indistinct in the same object . . . . . 42 



of objects, intermission in ..... . . .43 



seat of, investigated ....... . . 44 



seen single with two eyes, reason of its being . . . . .45 



'rtho wheel, descriptions of . . ... HYDRAUL. 23. MECH. t. i 22 



proper form and number of its float-boards . MECHANICS, t. \. . 22 



nt of the theory of ... OPTICS . . 32 



.... MECHANICS, t. ii. . 62 



e d . HEAT . . 52 



g of . . . MECHANICS, t. ii. . 26 



HEAr . . 5i 



... 52 



/fheat .... HEAT . . 25 



agent . . . MECHANICS, t. i. . 19 



D 



