STATISTICS OF WHEAT CULTITBE. 233 



its power of affording nourishment to the human system. It is in truth quite 

 impossible to arrive at any other than approximate results from the operations 

 of chemistry, as to the amount of nutriment contained in a given quantity or 

 weight of any article of food.* 



It is perhaps not irrelevant to notice in this place some of the researches 

 which have recently been made upon fermentation, and particulaily its effects 

 in the manufacture of bread. It appears that when this process is brought about 

 by the addition of yeast or leaven to the paste or dough, the character of the 

 mass is materially altered. A larger or smaller proportion of the flour is vir- 

 tually lost. According to Dr. William Gregory the loss amounts to the very 

 large proportion of one-sixteenth part of the whole of the flour. He says, " To 

 avoid this loss, bread is now raised by means of carbonate of soda, or ammonia 

 and a diluted acid, which are added to the dough, and the effect is perfectly 

 satisfactory. Equally good or better bread is obtained, and the quantity of flour 

 which will yield fifteen hundred loaves by fermentation, furnishes sixteen hun- 

 dred by the new method, the sugar and fibrin (gluten) being saved." (" Outlines 

 of Chemistry," p. 352.) 



Another author, Dr. R. D. Thomson, states, as the results of his experiments 

 upon bread produced by the action of hydrochloric acid upon carbonate of soda, 

 " that in a sack of flour there was a difference in favor of the unfermented bread 

 to the amount of thirty pounds thirteen ounces, or in round numbers, a sack of 

 flour would produce one hundred and seven loaves of unfermented bread, and 

 only one hundred loaves of fermented bread of the same weight. Hence it ap- 

 pears that in the sack of flour by the common process of baking, seven loaves, 

 or six-and-a-half per cent, of the flour are driven into the air and lost." (" Ex- 

 perimental Researches on the Food of Animals," &c., p. 183.) 



The only objection to the general introduction of this process seems to be the 

 degree of care and accuracy required in properly adjusting the respective quali- 

 ties and quantities of acid and alkali, and which could seldom be attained even 

 by those who are largely engaged in the manufacture of bread. 



I cannot leave this subject without adverting to a practice which has prevailed 

 in England and France, and perhaps also in this country, of steeping wheat 

 before sowing it in solutions of arsenic, sulphate of copper, and other poisonous 

 preparations. 



The result has been that injurious effects have often followed, both to those 

 who are employed in sowing such grain, and to those who have used the bread 

 manufactured from it. The great importance of the subject led to the appoint- 

 ment of a commission at Rouen, in Fraace, in December, 1842, having for its 

 object to determine the best process of preventing the smut in wheat, and to 

 ascertain whether other means less dangerous than those above noticed were 

 productive of equally good results. The labors of this commission extended over 

 ths years 1843-' 44-' 45, and the experiments were repeated two years following 

 on the farm of Mr. Fauchet, one of the commission, at Boisquilaume, in the de- 

 partment of the Seine Inferieure. 



The results arrived at by this commission are 1st. That it is not best to sow 

 seed without steeping. 2nd. That it is best to make use of the sulphate of soda 

 and lime process, inasmuch as it is more simple and economical, in no way in- 

 jurious to the health, and yields the soundest and most productive wheat. 

 3rd. That the use of arsenic, sulphate of copper, verdigris, and other poisonous 

 preparations, should be interdicted by the government. (" Gardeners' Chronicle," 

 January 6th, 1849, pp. 10 and 11.) 



Composition of wheat and wheat flour, and the various modes of determining 

 their nutritive value. In my former report it was stated that the analyses of the 

 various samples of wheat, the results of which were there given, had been chiefly 

 directed to the determining the amount of rough gluten which they contained. 

 My reasons for adopting this plan, and the arguments in favor of its general 

 accuracy, as compared with other modes of analysis, and especially that by which 

 the ultimate composition is ascertained, were also detailed. A more full exami- 

 nation of this subject has served only to strengthen the opinion already expressed, 

 that for the great purpose to be answered by these researches, the process which 



* A Treatise ou Diet and Kegimen, by Win, Heurv Robertson. M.I)., vol. i. p. 1 W. 



