Elm Tree y called Ulmin. 6^ 



in no degree altered, but they had acquired the blue and yellow 

 colours of heated steel, of which they had likewise the metaK 

 lie aspect and lustre, and could difficultly, if at all, have been 

 distinguished by the eye from heated steel-filings, or frag- 

 ments of slender watch-springs. Water immediately destroyed 

 their metallic appearance. 



Muriatic acid, poured on, caused a strong effervescence, and 

 formed muriate of potash, which, freed from all charcoal, and 

 made red hot, weighed 0.6 grain, corresponding to J^ of 

 potash in ulmin. 



These experiments assign about -f- for the quantity of potash 

 in ulmin, but as it is impossible to operate, on so small a scale, 

 on such substances without loss, it is probable that it even 

 exceeds this proportion. 



5. The substance separated from ulmin by acids has the 

 following qualities : 



It is very glossy, and has a resinous appearance. 



In lumps it appears black, but in minute fragments it is 

 found to be transparent, and of a garnet-red colour. 



It burns with flame, and is reduced to white ashes. 



Alcohol dissolves it, but only in very small quantity. 



Water likewise dissolves it, but also only in very small 

 quantity. Acids cause a precipitate in this solution, though 

 this resin-like matter appears neither to contain any alkali, 

 nor to retain any of the acid by means of which it was ob- 

 tained. 



Its solution in water seems to redden turnsol paper. 



Neither ammonia, nor carbonate of soda, promote its solu- 

 tion in cold water. 



On adding a small quantity of potash to water in which it 



Ka 



