INFLUENCE OF AMMONIA ON QUALITY 



125 



In some other experiments the sulphate of ammonia was 

 applied to the land with good results as early as March or 

 April. 



3. Influence of Ammonia Salts on Quality. Much 

 that has already been said about mangel wurzel under this 

 head might be recapitulated here. We cannot greatly in- 

 crease the size of a turnip crop without some deterioration in 

 the feeding quality of the roots ; with moderate manuring the 

 alteration in composition is but small, but when a heavy dressing 

 of dung and artificial manures is employed the deterioration 

 may become considerable. 



In the following table will be found the percentages of 

 water, ash, and nitrogen in the roots of white turnips and 

 swedes grown at Rothamsted with various manures. The 

 results for turnips are the mean of two years, 1847-48 ; those 

 for swedes are the mean of four years, 1849-52. (Watts' 

 Dictionary of Chemistry, Second Supplement, p. 1056). 



TABLE XLII. 



COMPOSITION OF WHITE TURNIPS AND SWEDES GROWN WITH 

 VARIOUS MANURES AT ROTHAMSTED. 



A beneficial effect of the potash on the quality of the roots 

 is plainly indicated by these figures. The addition of much 

 ammonia salts to superphosphate leads to the production of a 

 more watery turnip, but when alkalies are supplied the deterio- 



