AGRICULTURAL TEXT-BOOK. 61 



many circumstances, such as (a,) the soil; (b,) the manure 

 used ; (c,) the variety ; (d,) the climate ; (e,) the time it is 

 harvested, &amp;lt;fec. The following analysis by Sprengel may be 

 taken as an average. 100,000 parts dry wheat contain 1177 

 parts of ash or inorganic matter; the same quantity of wheat 

 straw contains 3518 parts of ash. They consist of the follow 

 ing substances : 



GRAIN. STRAW. 



Potash, - - 225 20 



Soda, 240 29 



Lime, - 96 240 



Magnesia, - - 690 32 



Alumina, 26 90 



Silica, - 400 2870 



Sulphuric Acid, - 50 37 



Phosphoric Acid -40 170 



Chlorine, 10 30 



1777 3518 



161. Analysis of the organic, or combustible portion. 100 

 parts of wheat in its natural state contain. ( Gregory.) 



Albumen, ...... 3 Q 



Gluten, - - - 9.9 



Starch, - - . 55.7 



Gum, Dextrine, Pectine and Sugar, - - -4.6 



Fibre and Husk, . -11.9 



82.31 



162. Or according to another analysis (Gregory,) the parts 

 may be thus divided : 



Water, . . 12.9 



Organic Matter, ....... 35.3 



Ash, - . . Ii9 o 



163. The influence of variety of seed and mode of culture 

 are shown by the following results of the examination by Bous- 

 singault of several varieties of wheat grown in the Botanic 

 Garden at Paris : 



