26 GENERAL INDEX. 



Page 



Direction of motions, various modes of altering . . . MECHANICS, t. ii* 53 59 



visible objects, concerning .... OPTICS . , 42 



Discharge pipes, proper form of described .... HYDRAULICS . 3 



of pumps, calculations on the .... . . 16 



Dispersion of light, concerning ..... OPTICS . . 24 



Dispersive powers of bodies with regard to light, table of . . . .25 



Distillation, process of, described . . . * . HEAT . . 56 



of fluids in vacuo ...... . . .58 



Distinct and indistinct vision in the same object, cause of . OPTICS . . 42 



Diverging and converging beams of light, phenomena of . . . . .67 



Do/lond's achromatic telescope, description of . . PREL. TREAT. 23. OPTICS 27 



Double axle and wheel, described . . . MECHANICS, t. ii. . 24 



.. rack . 51 



Double refraction of light, general account of ... POLAR. OF LIGHT . 1 



laws of, in crystals . . . 3 7 



circular ..... -. 7 



communicable by heat and pressure . 48 



.. to glass plates by mechanical force . 55 



productive of polarisation of light . , . 14 



its connexion with polarisation . . 29 



law of, in crystals with two axes . . 29 



combination of axes of . . . 29, 30 



new species of in Analcime . , . . 39 



Doubly refracting crystals, absorption of light in ... < . . 46 



structure of .... . . 56 



. . . . influence of heat upon . . . . . . 62 



force in spheres, spheroids, and tubes of glass, 

 distribution of ..... 



glass plates, combination of ... 

 structure rendered permanent in glass . 



produced by evaporation and induration 

 Double system of coloured rings produced by certain crystals . 



possessed by certain crystals 

 Draught, angle of, considerations on . . . . . 



Drill-bow, manner of its motion ...... 



Driving piles, machine for, described .... 



Duck, description of its bill ...... 



Duration of the impressions of light on the eye ascertained 

 Dynamics, definition of the science ... 



51 



. 55 

 52 



. 53 

 23 



. 25 

 1926 

 59 



. 51 



PRELIMINARY TREAT. 31 



OPTICS . . .44 



PREL. TREAT. 12. MECH. t.i, 1 



MECHANICS, t. iii. 

 t. ii. 



Earth, concerning its approach to a falling body . 

 Eccentric, a machine for producing parallel motion, described 

 pump, description of . . . . . . 



Echoes, the cause of described ...... 



Eckhardfs capstan, description of ..... 



Economical application of Steam ..... 



Economy of ants and bees, description of . . . . 



of beavers ....... 



Effect, of light on vegetables ..... 



.. in changing the colours of bodies . 

 different kinds of, produced by machinery 

 of velocity upon friction ..... 



of combining and crossing rectangular plates of glass 

 produced by altering the form of glass plates . . 

 . . of pressure on regular crystals .... 



Efficacy, mechanical, of machines in general, observations on 

 of pulleys . % . . 



of wheels and axles .... 



icker, or toucan, description of that bird . 



: fluids defined ....... 



their capacities for heat investigated 



compared with atmospheric 



air, table of 

 force of vapour and steam of water, tables of . 



. . of different vapours, compared with each other, table of 

 ity of air, concerning the 



shewn *~ u - . I i the weigh' 

 of fluids in g 



MECHANICS, t. i. 



. t. ii. . 



HYDRAULICS . . 

 PNEUMATICS . 



MECHANICS, t. ii. 

 HEAT 

 PRELIMINARY TREAT. 



OPTICS 

 MECHANICS, t. ii. 



t. iii. 



POLAR. OF LIGHT 



MECHANICS, t. 



PRELIMINARY TREAT. 

 PNEUMATICS . , 

 HEAT 



8 



59 

 16 

 30 

 24 

 52 

 28 

 29 

 27 

 64 



1 



31 

 55 

 52 

 56 

 13 

 33 

 24 

 32 



1 

 36 



38 

 48 



