CONTENTS. Vli 



Separation of substances by crystallisation, . . ^4 



Tests for iron and for acids, ... 65 



Sugar candy : crystallised baskets, ... 66 



Frosted windows, ..... 67 



Influence of solution on colour, .... 68 



Supersaturated solutions, .... 68 



Different solubility in different solvents, . . 69 



Separation of solids by solvents, ... 71 



Solubility of liquids in solids, ... 72 



Penetration of gold by mercury, . . .: 72 



CHAPTER VI. Solution of Gases in Liquid Solvents and 

 Separation of Gases from Solution, no Chemical Action 

 taking place, . . , . . . 74-87 



Gases really the vapours of volatile liquids, . . 74 



Aerated waters and beverages. Carbon dioxide, . 75 



Carbon dioxide extinguishes a lighted candle, . . ; 75 



Gasogenes : extincteurs, .' ,' , . 76 

 Circumstances modifying the solubility of gases in 



liquids, . . . . . 79 



Solubility of gases proportionate to pressure, . . 79 



Solubility decreased by rise of temperature, . . 80 



Ammonia gas. Collection by displacement, . . 80 



Ammonia fountain, . * . . . 81 



Ammonia gas absorbed by ice, .... 83 



Separation of gases by means of solvents, . . 83 



Passage of gases through moist membranes, . . 85 



Supersaturated solutions of gases, . . . 85 



CHAPTER VII. Solution of Gases in Solid Solvents and 

 Separation of Gases from Solid Solutions, no Chemical 

 Action taking place, . ' . . . . . 87-91 



Occlusion of gases, . . . . 87 



Palladium eels, . -. . . . 88 



Chemical activity of gases enhanced by occlusion, . 89 



Passage of gases through solids,. ... . 90 



Hydrogen separated from coal gas, . . . 90 



CHAPTER VIII. Miscibility of Liquids, or Mutual Solu- 

 bility of Liquids in one another, no Cliemical Action 

 taking place, . . . . . 91-106 



Different degrees of mutual solubility of liquids, . 91 



Miscibility of molten metals, .... 93 



