1886.] PUBLIC DOCUMENT — No. 33. 95 



engaged in the preparation of horse radish, with vinegar, for 

 family use. The roots had evidently lost some of their orig- 

 inal moisture by storing, at the time of their examination. 

 One hundred parts of the fresh roots contained : — 



Moisture at 100° C, 76.68 per cent. 



Dry Matter, 23.32 



Nitrogen in Dry Matter, .36 " 



Sulphur in Dry Matter, 06 



Crude Ash in Dry Matter, 1.87 " 



The crude ash — 1.87 — consisted of 0.71 parts of insolu- 

 ble silicious matter (including, most likely, some soil), and 

 of 1.16 parts of soluble mineral constituents of plant food. 



Relative proportion of essential ash constituents, soluble 

 in acids, sulphur and chlorine excluded : — 



Magnesium oxide, 8.24 per cent. 



Ferric oxide, 2.13 " 



Calcium oxide, • . 13.47 " 



Sodium oxide, 10.29 " 



Potassium oxide, 62.06 " 



Phosphoric acid, 3.81 " 



100.00 



The roots contain, besides a notable amount of nitrogenous 

 constituents, a series of valuable non-nitrogenous substances, 

 as starch, sugar, gum, and organic acids, — a circumstance 

 which cannot fail to impart to them a considerable nutritive 

 vaiue, equal, if not superior, to several of our most valuable 

 root crops. Their peculiarity consists, mainly, in the 

 presence of some sulphur-containing organic constituents 

 (myrosin, etc.), which cause, in the fresh and crushed roots, 

 the production of a sulphur-containing, volatile compound. 

 The latter resembles, in odor and taste, the volatile mustard 

 oil (^liliodanallyl) . Some investigators assume their iden- 

 tity. The amount of this product, according to the state- 

 ment of good observers, depends largely, either on the 

 general character of the soil, or on the presence of some 

 peculiar constituent in the latter. It would be not without 

 interest to study the effect of gypsum, or of sulphate of pot- 

 ash, as a special fertilizer, on the character of the roots 

 raised in their presence. 



