ISO 



its oxygen, and so completing the vitrification of the iron 

 or other colouring ingredients. It is used as a pigment 

 or an ingredient in printer's ink, and to procure oxygen 

 gas from, for many purposes, viz. as a medicine ; or for 

 oxygenizing muriatic acid for bleaching, &c. About two 

 quarts of this gas may be obtained from an ounce of oxide 

 of manganese. 



