1835.] on Malt. 445 



immersed in it would vegetate. Hence, in water, 122° may 

 be considered the highest limit at which it is possible for 

 barley to grow. But the temperature varies according to 

 the media through which the heat is communicated. Thus 

 these seeds if exposed to a temperature above 143J° in 

 vapour, or 167° in dry air, are deprived of their vegetating 

 properties. While wheat, barley, oats and rye, when kept 

 in hot sand possessing a heat of 113°, would not germinate. 

 Immersion in water of the temperature of 167° for 15 

 seconds was sufficient to destroy the power of germination 

 in most instances ; but this invariably occurred, if the ex- 

 posure to this high temperature was protracted for 5 

 minutes. The method in which the heat operates in these 

 cases, appears to be in some measure elucidated by the 

 researches of Biot, Persoz, and Raspail, who observed that 

 the temperature 167° is that at which the grains of starch 

 burst. Hence, it appears, that in dry air barley may be 

 exposed to a range of temperature equivalent to 205° at 

 least, and may still retain its germinating powers unim- 

 paired. 



We have two quantitative analyses of barley, one by 

 Einhof and the other by Proust. The following are their 

 results. Einhof obtained from Hordeum vulgare. 

 Starch not quite free from gluten . . 67*187 



Volatile matter 9*375 



Saccharine matter 5-208 



Husk with some gluten and starch . . 6*770 



Mucilage 4*583 



Gluten 3*515 



Albumen 1*114 



Phosphate of lime and loss .... 2*248 



100*000* 



Proust obtained, Yellow resin ... 1* 



Gum ...... 4* 



Sugar 5* 



Gluten 3 



Starch ..... 32* 



Hordein 55* 



100-f 



* Gehlen, vi. 83. Thomson's Chemistry, iv. 262. 

 t Ann. of Phil. xii. 201. 



