ts 
Experintents 61 the Nutrition of Plants. »95 
hoot be difengaged in fuch a manner as to produce fome effect 
on plants. At firft he obtained no effeét; but having wa- 
tered this box with diluted fulphuric acid; he remarked that 
the barley vifibly grew falter in this box than in thofe not 
watered in the ase manner *, 
Of all the mixtures which he tried for fowing, none ap- 
peared to him better than that of equal parts of charcoal, 
mould, and fand, moiftened with water filled with infufion 
animals, which may be eafily obtained by fieeping flax in 
the water deftined for that purpofe. He obferves, on this 
occafion, that, of all the fubftances he tried, flax is that which 
furnifhes the moft of thefe animalcule. An incredible mul- 
titude of them are found in the water in which women dip 
their fingers when they are employed in {pinning. The 
Water put into a veffel for that ufe in the mornifig, is found 
filled with them in the evening. The author afcribes to 
thefe {mall animals a much greater influence on vegetation 
than has hitherto been believed. ae, 
Haffenfratz relates, that he could not make plants vegetate 
‘well in fimple earths. The author afferts, that he hall great 
fuccefs when he reared them im pure filex, quartzy fand thrice 
wafhed, fine fand from the fea-fhore, &e. But thefe plants 
continued ftunted and pale, and their roots were twice as 
‘long as the whole of the part above the earth. In charcoal, 
on the other hand, the parts were, large and vigorous; they 
‘were of an exceedingly dark colour, and their reots were not 
a fixth part of the length of the plant itfelf +. 
Coal-afhes, on which the German and Englith farmers 
“beftow fuch praife, deftroy the plants if the foil contains an 
eighth part of that admixture. The leaves become faded, as 
~ ™ The fulphuric acid cold does not difengage the oxygen of the oxyd 
of manyanefe: befides, according to the experiments of Ingenhous, this 
acid alone, in fmall quantity, feems to have the property of rendering ve- 
“getation more active. 
+ The firft refults ave perfeétly fimilar to thofe obtained by C. Haffens 
fratz.. In regard tothe fecond, they depend om the purity of the chara 
coal employed, which may contain wood undecompoled, and confequently 
‘ difpofed to putrify, and to yield a liquid which may hold the carbon ia 
folution. 
Hhe if 
