On the Fecula of Green Plants. isf 



IV. A' hundred parts of the dry fecula of hemlock trans- 

 mit to alcohol from 15 to 16 of green resin. When taken 

 trom repeated infusions to which it has been subjected, it 

 remains of an earthen gray colour, and alcohol is never able 

 to bleach it. Sage, who was well acquainted with the na- 

 ture of feculie, found some which gave even a third of their 

 weight of resin : to exhaust them with ease, it is necessary 

 to throw them still moist Into spirit of wine; the spirit 

 then penetrates and attacks them in every point : but this 

 is much more difficult when they have been rendered cor- 

 neous by desiccation. 



Parmentier, I think, was the first who doubted, and with 

 reason for his time, that alcoholic tincture of feculse is re- 

 sinous, because it is not precipitated by water. However, if 

 it be considered that water can never detach it from gluten, 

 that alcohol, oils, and fat, have exclusively this property ; and 

 that this substance, when separated from alcohol and con- 

 centrated in itself, is a fat tenacious body insoluble in water, 

 it will be found that there is no product in vegetables which 

 it approaches so much as the resinous : but we shall here 

 show, that to determine in it more perfectly this character, 

 nothing is necessary but to furnish it with a little o,%ygen. 



The oxygenated muriatic acid in a few days renders green 

 resin white and firm ; it then suffers itself to be drawn out 

 in threads like boiled turpentine, and its dye mixes rea- 

 dily with water : but if the green part of fecula; belonged 

 to those coloured juices which are found in the ingredients 

 proper for dyeing, oxygen would not convert it into a resin. 

 But at present, since observation has taught us that we ought 

 no longer to establish between vegetable products such ri- 

 gorous limits as formerly; since we see them so often con- 

 founded by intermediate qualities, we are not astonished to 

 find that a resin carried to its maximum of divisibility can 

 associate with water. Do Vvc not see camphor, essential, 

 animal, and vegetable oils, sarcocolla, &c. dissolve com- 

 pletely in water? We shall not, however, for this reason, 

 lake such products from that classification which has been 

 assigned to them by analysis. 



Green fcculac; assume in oxygenated muriatic acid that 

 colour of dead leaves which lorms the mourning of vegeta- 

 tion during the winter, and their dye becomes very turbid 

 in water. Let us deduce then from all this, that if the co- 

 louring part of feculce cannot resist water when transmitted 

 by alculi(jl, it is no less in rcgasd to its other qualities a sub- 

 ttance absolutely resinous ; and though this jjroduct, one 

 4)f the moat c^riogiS i{x the vegetable kingdom, since it em- 

 - ■ - bi.llishe» 



