ON THE FECU1A OF GREEN PLANTS. jjj 



dried, yields by diftillation the produ&s of white wood, of 

 linen, that is to fay, nothing ammoniacal. It is the woody 

 part which ufually accompanies the fecula in confequence of 

 the trituration. 



This folution has all the characters of an animal folution ; The folution 

 it exhales ammonia, an odour which is that of a woad vat ; ra ^ er$# 

 it blackens tha filver evaporating bafon, and emits, by the 

 action of acids, an effluvium which darkens the writing of 

 white metals. 



But in this cafe, as in the foap of wool, great part of the But the fecula 

 fecula experiences a lofs which deranges the nature and pro- cann r ot ® re - 

 portion of its radicals. Acids only feparate a fmall quantity 

 of the fecula. The remainder acquires an extractive cha- 

 racter which difpofes it to unite with water. Neither alcohol 

 nor acids can feparate this new extract from falts. It is of a 

 fawn colour, and muriate of tin precipitates from it a dulky 

 lake. 



With refpeft to the other, when collected and warned on Properties of the 

 the filtre, it is worthy of notice that it has not loft the pro . fcp«*ed natter, 

 perty of hardening by the heat of boiling water. 



Alcohol acquires a deeper green from the precipitated 

 fecula than from that which is frefti. This arifes from the 

 refin, which not being deftruclible like the gluten, is united 

 in greater quantity to that which efcapes the deftruclion. As 

 to its other properties, this fecula, by diftillation, yields 

 ammoniacal products. 



XI. An acid of 18 or 20 degrees difengages azote abund- Adds feparate 

 antly from green fecula ; a ftronger acid diuolves them with J**J^ ^JJ"J 

 facility, and feparates a little powder which is the ligneous 

 fragments of the plant. 



However fparingly the nitric acid is ufed, it is but feldom 

 that cryftallifed oxalic acid can be obtained. It is refolved 

 into carbonic acid and water. 



The folutions of fecula always contain the yellow bitter 

 principle pi' Welter, fulphuric acid, benzoic acid, oxalate of 

 lime and fat. If the folution of a fecula containing iron, 

 fuch as the folanum lycoperiicum, be precipitated with acetite 

 of lead, a powder compofed of oxalate and phofphate of lead, 

 and oxide of iron is obtained. On heating it with the blow- 

 pipe it burns, even the lead is diffipated and nothing remains 

 but a globule of phofphate of iron. 



When 



