Mr. Sorby's Chemical Analysis, ^c. 331 



able precipitate of subnitrate was formed^ when on adding 

 acetic acid the whole of the phosphate alone was left insoluble, 

 which, after standing awhile, was collected on a filter, washed, 

 dried, ignited and weighed, and the amount of phosphorus 

 obtained by calculation. That this method is correct, and that 

 the phosphate which is thus obtained is Pbg P Og, I have 

 proved by experiment. 



It must be borne in mind that the amounts given below 

 are those of sulphur and phosphorus, I having thought it right 

 to give them as such, and not as sulphuric and phosphoric 

 acids, since most certainly they do not exist invariably as 

 such or as their salts in plants, and I therefore see no reason 

 why they should not be given as elements, like the amounts 

 of carbon, nitrogen, oxygen and hydrogen as usually given 

 in such analyses. 



The plants analysed, with only three exceptions, viz. the 

 rye, mangel-wurzel, and hops, were obtained from the fields 

 in which they were growing by myself, and hence I can vouch 

 for their freedom from impurities, and have no doubt the 

 others were as much so as possible. 



Table of the Amounts of Sulphur and Phosphorus in various 

 Agricultural Crops, calculated in 100 parts, dried at 212° F. 

 until the weight remained constant. 



Name of Plant, &c. 



Four species of grass {Poa palustris and trivialis, \ 



Fesfuca pralensis, Cynosurus cristatus) j 



Rye grass {Lolium perenne) 



Italian rj'e grass 



Red clover {Trifolium pretense) 



Ditto 



Very fine white clover (7". repens) 



Ordinary ditto 



Ver)' fine trefoil {Medieago lupulina) 



Lucem {M. saliva) 



Ditto 



Ditto , 



Lints {Vicia saliva) 



Kidney potatoes {Solatium luberosum) 



Ditto, tops 



Ditto, fruit 



American native potatoes 



Ditto, tops 



Carrot {Daucua carota) 



Ditto, tops 



Mangel-wurzel {liela allissima) 



Ditto, tops 



Earl v yellow-top turnip {Brassica rapa) 



Ditto 



Ditto, tops 



Ditto 



Sulphur. 



•165 



•310 

 •329 

 •107 

 ■087 

 •099 

 •151 

 •136 

 •274 

 •452 

 •293 

 •178 

 •094 

 •389 

 •071 

 •082 

 •206 

 •092 

 •745 

 •058 

 •502 

 •351 

 •421 

 •758 

 •615 



Phosphorus. 



•164 



•183 

 •145 

 •149 

 •131 

 •183 

 •139 

 •052 

 •046 

 •215 

 •353 

 •183 

 •213 

 •357 

 •597 

 •212 

 •483 

 •255 

 •382 

 •190 

 •293 

 •352 

 •346 

 •360 

 •380 



