176 WHEAT. 



The quantity of gluten ind albumen contained in these samples of 

 flour is much larger than that usually indicated ; I have given rea- 

 sons which explain, to a certain extent, this difference. I ought to 

 add, however, that the varieties of wheat, the flour of which was 

 analyzed, were all grown in the rich soil of the garden, a circum- 

 stance which, as Hermbstadt has shown, exerts the most powerfu. 

 influence in increasing the quantity of gluten in wheat. 



It was already known, from the experiments of Tessier, that the 

 proportion of gluten in the same species of wheat might vary in the 

 ratio of from 12 to 36 per cent, of the weight of the flour, according 

 to the nature of the soil and the quantity of manure. But it was 

 Hermbstadt who first made truly comparative observations on the 

 action of the excrements of diflferent animals on the culture of the 

 cereals. 



The excrements made use of by this able cultivator in his inquiries 

 w^ere always dried in the air at a temperature of 12|° C. (54^° F.,) 

 and equal areas of the same soil were sown with equal weights of 

 winter wheat, and had a similar dose of manure of one kind or an- 

 other spread over them. One hundred parts of the flour obtained 

 from wheat thus grown yielded : 



Bran, soluble mai- 



- Gluten. Starch, ter and moiiture. 



With human urine 35.1 39.3 25.6 



" bullock's blood 34-2 41-3 25.5 



" human excrement 33.1 41.4 25.5 



" sheep's dung 22-9 42.8 34-3 



" goat's ditto 32.9 42.4 24.7 



" horse ditto 13.7 61-6 24-7 



" pigeon's ditto 12.2 63-2 24-6 



" cow's ditto 12.0 62.3 25.7 



Soil not manured 9-2 66.7 24-1 



It is apparent, therefore, that in general, for the exception onl 

 refers to the pigeon's and the horse dung, the wheat grown in groun 

 manured with the most highly azotized matters yields the target 

 quantity of gluten. 



By way of adding to and confirming these conclusions of Hermb 

 stadt, I shall give the results of an experiment of my own, made i< 

 1836, in which the same variety of wheat was grown in the opev 

 field, and in garden ground very highly manured. The grain wjm 

 analyzed after having been dried at 110° C, (230" F.,) and gave : 



From the open field. From the garilen gnuad. 



Carbon 46-10 45.51 



Hydrogen 5.80 5.67 



Oxygen 43.40 43.00 



Azote 2.29 3.51 



Ashes 2.41 2.3 1 



100.00 100.00 



In the produce of the garden there were 21.94 — very nearly 22 

 per cent, of gluten and albumen ; in that of the open field no more 

 than 14.31 per cent, of the same principles. 



Davy was of opinion that the wheat of warm climates was richer 

 in azoti'/ed principles than that of temperate lands. Southern coun- 

 tries are known to produce harder, tougher grain, the flour of whicb 



