X ELEMENTS OF LABORATORY WORK 



(50. Change of temperature in an electric circuit . . . .87 

 Table of approximate relative conductivities with mercury as 



unity 88 



Kesistance of copper wire of various sizes . . . .89 



61. Formation of a current by change of temperature . . .90 

 Additional exercises and questions ...... 91 



CHAPTER VI 



OBSERVATIONS WHICH LEAD TO THE THEORY THAT ALL 

 MATTER IS MADE UP OF VERY SMALL SEPARATE PARTICLES 



62. The gradual re-arrangement of matter when some liquids are 



placed in contact 93 



63. The gradual re-arrangement of matter when some solids are 



placed in contact with some liquids . . . . 94 



64. The temperature-change attending solution, and the variation 



of rate of diffusion with temperature . . . . .96 



65. The quantity of a solid dissolved varies with the temperature 



of the solvent 96 



66. The gradual re-arrangement of matter when different gases are 



placed in contact 98 



Table of solubility of air in water, and table of solubility of 

 other gases in water and alcohol 99 



67. Atmospheric pressure and its variations . . . ? . 99 



68. Use of the cistern barometer . 101 



69. The volume of a given mass of air varies inversely as the 



pressure ... . . . . . . . . 103 



70. Graphic representation of correlative changes by diagram .104 



71. The variation in volume of a given mass of air for a given 



change of temperature 106 



72. The temperature-changes resulting from volume-changes in 



gases . . 107 



73. The pressure of aqueous vapour at different temperatures, the 



measurement of 109 



Table of pressure of aqueous vapour at different temperatures 110 

 Table of boiling-points of some saturated solutions . .110 



74. Enunciation of Avogadro's theory Ill 



Additional exercises and questions 113 



