Bibliography. 191 



ing watev, but not sufficient to brown the glazed papei* on which the 

 operation was performed, lost on being burned, 6.90 grains of vege- 

 table matter. 



"The soil was then mixed with four times its weight of carbonate 

 of potash, and was fused at a full red heat in the platina crucible, so as 

 to render the whole soluble in water. The mass was then dissolved 

 out from the crucible by means of boiling water, and was acidulated 

 with muriatic acid, and then evaporated to entire dryness, so as to 

 render the silica insoluble. The whole mass was then rubbed to a 

 fine powder with an agate pestle, and moistened with muriatic acid. 

 Then all the matters soluble in acidulated water were taken up by 

 means of distilled water. The whole was then poured on a double 

 filter, and the silex was collected, washed until pure, dried and igni- 

 ted ; the second filter being burned and counterpoised against it. The 

 silex weighed while warm amounted to 47.39 grains. The solution 

 that had passed the filter was then treated with a little nitric acid, and 

 boiled to peroxidize the iron. Ammonia being then added in slight 

 excess, the alumina and peroxide of iron being precipitated together 

 were collected, and washed thoroughly for several days with boiling 

 water, until the water came through the filter pure. The alumina 

 and peroxide of iron were then separated by means of a boiling so- 

 lution of pure potash, in a silver crucible. When all the alumina 

 was taken up by the potash, and the iron had subsided, it was filtered 

 in a double filter, and the peroxide of iron being collected, washed, 

 dried, ignited, and weighed, amounted to 11.20 grains. The alumina 

 was separated by neutralizing the alkaline solution, and was then pre- 

 cipitated by means of a solution of carbonate of ammonia. When 

 collected on a filter, washed, dried, ignited, and weighed, it amounted 

 to 32.10 grains. 



"The solution from which the alumina and iron had been separa- 

 ted, was then treated with a solution of oxalate of ammonia, and the 

 lime was precipitated in the state of an oxalate, and when collected, 

 washed, dried, ignited, and converted into a carbonate, weighed 2.85 

 grains. The remaining solution being tested for magnesia, gave no 

 trace, but a little manganese was detected by hydrosulphate of am- 

 monia. 



" Results of this analysis of the dry soil: 



Vegetable matter, ..... 6.90 



Silex, ....... 47.39 



Alumina, ....... 32.10 



Peroxide of iron, . . . . . 11.20 



Phosphate and crenate of lime, . . . 2.02 



Manganese, traces, 



99.61 



