42 



ANALYSIS OF THE ONIONS. 



A recent analysis, under the direction of Prof. Goessmar 

 oi the ^Massachusetts Agiicultural College, gives the following 

 as the principal constituents of the onion : 



Air dry onions without leaves were found to consist of : 

 Water (at ioo° to iio° C.) . . 89.20 per cent. 

 Dr}' vegetable matter . . . 10.80 

 and contained the follovdng amounts of — 



Nitrogen ..... 0.212 per cent. 



Sulphur ...... 0.048 



Ash . - . . . . . 0.436 " 



The percentages of the principal constituents of the ash 

 were : 



Potassium oxide .... 3S.51 per cent. 

 Sodium oxide .... 1.90 



Calcium oxide . . . . 8.20 

 ]Magnesium oxide . . , . 3-65 " 

 Sesquioxide of iron . . . 0.58 

 Silicic acid . . . . . 3.33 



Phosphoric acid . . . . 15.80 " 

 Sulphuric acid not determined. 

 .In the above table Potassium oxide. Sodium oxide, Cal- 

 • cium oxide and Magnesium oxide, mean practically pure- 

 Potash, Soda, Lime and ^Magnesia. 



I infer from the table that of the three grand essentials in 

 manure, Nitrogen, Potash and Phosphoric acid, the onion 

 requires about equal quantities of the two former and half as 

 much of the latter. 



I trust this contribution will prove acceptable. 



TAMES J. H. GREGORY. 



Marblehead, ]Mass. 



