212 THE YEAR-BOOK OF AGRICULTURE. 



of the plant, as pulled from the field in the usual state of maturity, when the seeds contained 

 in the capsules begin to assume a brown color, shows that it contains starch, which can be 

 readily extracted by placing the stems, cut in pieces, in a powerful lever press, and moisten- 

 ing them with a small quantity of water. By allowing the expressed liquid to remain at 

 rest, the starch subsides, and assumes a purple tinge on the addition of a watery solution of 

 iodine. When, however, the flax straw is examined after it has remained exposed to the 

 air for several days in the shock, the liquid obtained by subjecting it to pressure., and washing 

 with water was found to afford no indication of the presence of starch. In the dressed flax 

 no trace of starch could be detected, and the discovery of the existence of a considerable 

 amount of grape-sugar is exceedingly interesting, as corroborative of the statement of expe- 

 rienced dressers, that, by storing up the steeped flax, as imperfectly dried by exposure to 

 the air for some weeks before proceeding to remove the adherent woody matters by scutch- 

 ing, the separation of fibre is greatly facilitated and its qualities improved. 



On the Deodorizing Properties of Charcoal. 



IN a recent communication to the Royal Agricultural Society, England, on the above sub- 

 ject, by Prof. Way, he remarked, that, independently of the noxious gases resulting from the 

 putrefaction of animal matter generally, and which consisted principally of sulphuretted 

 hydrogen and sulphuret of ammonia, each particular animal substance, excretion or other- 

 wise, had its peculiar odor, which although abundantly perceptible by the senses, and in 

 many cases, as in musk, almost inexhaustible was inappreciable in weight ; therefore, by 

 deodorizing a large amount of odor, it was to be inferred that a large amount of manuring 

 matter was thereby secured. He then enumerated the various single and double deodorizers 

 that had been employed. He referred to Sir William Burnett's excellent application of 

 chloride of zinc, and to the ordinary chloride of lime ; to gypsum, (sulphate of lime,) and its 

 conversion, in ammoniacal atmosphere, into sulphate of ammonia and carbonate of lime; to 

 the agreeable odor of pure ammonia, and its power of giving intensity to odors of a dis- 

 agreeable character, which intensity was lost when the ammonia was withdrawn ; to sulphate 

 of iron, (green copperas,) which, when powdered and thrown into tanks, turned black, on 

 account of the sulphuret of iron formed on the decomposition of the sulphuretted hydrogen 

 present. He then proceeded to the consideration of charcoal as a deodorizer. He gave an 

 interesting statement of the peculiar action of charcoals in general, arising, he believed, from 

 the great amount of surface their spherical interstices presented, and of the peculiar action 

 and superior value of animal charcoal over all others. He explained that in charcoals it was 

 not the amount of carbon they contained that constituted their value, but the mode in which 

 the carbon was distributed; that animal charcoal contained only 10 per cent, of real carbon, 

 while wood charcoal contained 90 per cent. He referred to the large amount of water (50 

 or 60 per cent.) which peat charcoal took up, and to the fallacious dry state of the manures 

 with which this water-carrier was mixed. He feared this mode of introducing water in a 

 latent state into manures, in many cases, gave a turn in the scale more in favor of the manu- 

 facturer than of the farmer. He doubted whether the peat charcoal could be used economi- 

 cally for the purpose of soaking up tank- water ; if not, he feared it would prove of no 

 advantage, in other respects, as a remunerative agent to the farmer. It had been long 

 before the public, but had not progressed in market value, as it would have done had its 

 application been successful. He considered it to lead to much error in practice that the 

 exact nature of the action of charcoal on ammonia was not better understood by the public. 

 Fresh-burnt charcoal would absorb a large quantity of ammoniacal gas, but it was a mistake 

 to suppose that it would consequently abstract ammonia from a liquid impregnated with it ; 

 on the contrary, water had the power of displacing from charcoal the whole of the ammonia 

 it had received in a gaseous state within its pores. Peat charcoal did not either take manure 

 or separate it from sewage ; it simply rendered manure portable. He exhibited a striking 

 experiment, showing the power of dry peat charcoal to arrest odors. Two open tumblers 

 were half-filled with the most offensive sewage matter Professor Way could obtain, and the 

 surface of each mass covered with a film of thin paper, and a thin bed of powdered peat 



