FARMERS' REGISTER— MOULD— EXTRACT OF MOULD. 



731 



tion, many generations of these animals succeed 

 each other, die and disappear, whilst their.eleraen- 

 tary parts concur with, and aid the ])henomena ot' 

 l)Utrel;ictiun. The water acts by dissolving the 

 soluble ])arts of organic matters, which are des- 

 troyed at the surface of the water by the action of 

 the air, and which absorb the oxygen which the 

 air yields to tiie water. In this manner, the in- 

 soluble parts are at first preserved from destruction, 

 which cannot take place without the help ol the 

 air; but by degrees the dissolved bodies arc de- 

 composed, oxygen penetrates into the water, and 

 Ihe destruction spreads over the insoluble parts. 

 But this reaction operates very slowly, and bodies 

 amassed at the bottom orwater so that the air 

 cannot jjcnetrate to them, can resist so well during 

 thousands of years, that their origin may after 

 that time be still recognized. 



Putrefaction at -the surface of the earth — Mould. 



The vegetable matters which rot at the surface 

 of the earth, finish by leaving a blackish brown 

 pulvendent mass, which has received the name 

 of inould, [humus.] 



All the vegetation of a year, which dies 

 at the arrival of winter, is converted by de- 

 grees to mould, which is mixed with the earth in 

 which the plant grew: whence it comes that the 

 extreme surface of the earth contains a greater or 

 less proportion of mould, which serves for the nu- 

 triment of the succeeding growth of plants. This 

 mould, such as it is found in the earth, is often 

 mingled with the products of a less advanced putre- 

 faction, or even with vegetable parts not changed, 

 principally, a great quantity of small roots. II" 

 we examine the mould, such as it is found in cul- 

 tivated soils, it is found to be in a mass very much 

 mixed; but it is always possible to extract the 

 parts which characterize mould. 



During the transformation of the vegetable 

 matters to mould, the first portion of their mass is 

 changed into a brownish black substance, which 

 presents all the characters of apothemc,* when w^e 

 have separated from it the unaltered extract, which 

 <be apotheme draws with it. The salts of such 

 acids as are of organic origin, contained in the ve- 

 getable matter, are destroyed, so that the elements 

 of the acid are resolved into water and carbonic 

 acid, whilst the base is combined with the sub- 

 stance analogous to apotheme, which makes part 

 of the mould. The salts of acids of mineral ori- 

 gin are preserved, unless they are soluble, in which 

 case the rain carries them off. In addition, mould 

 contains a substance but slightly soluble in water, 

 which colors the liquid yellow, and a carbonaceous 

 substance which is entirely insoluble, and which 

 apiiears to be one of the products of a destruction, 

 «till more advanced, of organic matters. 



To give an example of a completed formation 

 of a mould of vegetable origin, I shall here state 

 the results of an analysis to which Bracan not sub- 

 mitted some wheat, which had remained during 



* What B?rzelius calls apotheme, is "a deposite 

 slio-htly soluble in water, produced in an aqueous solu- 

 tion of vegetable extract during slow evaporation, and 

 containing a larger proportion of carbon, than does an 

 equal weight of extract." — Ed. 



many centuries in a damp vault, the issues Iroin 

 which were stopped up by cartli, and of which 

 the existence was forgotten, until by chance it wae 

 ag;un discovered. The grains had preserved their 

 form, and the brightness of their outside skm; but 

 they were black, and were reduced by the slightest 

 pressure to a black powder. The water with 

 which they were boiled was colored yellow, and it 

 left, after lieing evaporated, a s;iline nmss of a 

 brownish yellow, which burnt with slight cxjjIo- 

 sion wdicn heated, and which, besides the sub- 

 stance cited, soluble in water, contained nitrate of 

 potash, nitrate of lime, and a little of the muriates 

 of potash and of lime. The nitrates were the 

 result of the oxydation of the nitrogen contained 

 in the gluten and vegetable albumen, and of the 

 combination of the nitric acid thus produced, with 

 the bases previously combined with vegetable 

 acids. The weight of this mass soluble in water, 

 including the salts and all the other principles, did 

 not exceed H per cent, of the weight of the black 

 grain. When the jiart insoluble in water was 

 boiled in alcohol, a small trace of a brown sub- 

 stance was taken up, which remained ailer evapo- 

 rating the alcohol, and had the consistence of wax. 

 The mass, exhausted of its soluble parts by boil- 

 ing water and alcohol, was then heated slowly 

 with a weak solution of caustic potash, which be- 

 came saturated and colored oi' a blackish brown; 

 and this treatment was continued as long as new 

 potash lie took up any thing. This substance 

 was precipitated from "the eolution by an acid: it 

 was the body similar to apotheme which basal- 

 ready been mentioned, and of which the weight 

 amounted to 26i per cent. The portion of matter 

 insoluble in the alkali preserved the same appear- 

 ance. This exposed to the action of diluted mu- 

 riatic acid, yielded to it a certain quantity of lime, 

 of oxide of iron, and of phosphate of lime. The 

 residue was again acted on by pot;ish, which took 

 up a new and very large proportion of Ihe body 

 similar to apotheme. This was, after that, combined 

 with lime, and resisted in that state the action of 

 potash. This calcareous combination amounted 

 to 42 hundredths. The 30 per cent, remaining 

 consisted of a black carbonaceous matter, insoluble 

 in the solvent used. 



If cultivated soil is treated in the savne manner, 

 similar results will be obtained, with this difl'erence, 

 that the earthy matter of the soil is (bund mixed 

 with the products which are obtained, whilst no 

 soluble salts arc met with, they being generally 

 carried ofl' by the rains. 



To describe the constituent principles of mould, 

 it is necessary to designate them by parlicular 

 names. I will then call extract of mould the body 

 soluble in water, and I will give the name oi' geine* 

 to the matter similar to apotheme, which consti- 

 tutes the principal mass of mould. As to the 

 coally substance insoluble in water, alcohol, acids 

 and alkalis, 1 will designate it by the name of 

 carbonaceous mould. 



Extract of mould. 



We obtain this substance by drawing it from 

 the mould by the action of cold water, which be- 

 comes thereby colored j-ellow, and which leaves 

 after evaporation, a yelloAV extract of a bitter taste, 

 and from which some geine is sepamted when it 



*0r humin, as termed by other authors. 



