of the black Bronchial Glands, C^c. 163 



all of it was presently dissolved, except the coloured parts, 

 which retained their respective forms till the vessel was 

 shaken : then they were destroyed, and afforded a coating or 

 stratum of black matter on the surface. 



Having collected an adequate quantity of the colouring 

 matter in a powdery state, for examination, I performed a 

 number of experiments, but it seems needless to relate more 

 than a few decisive ones. 



1. A little of the well exsiccated black powder being sprink- 

 led upon fused nitrate of potash, deflagration took place as 

 with charcoal of wood, or with soot. 



2. The same phenomenon occurred with melted oxy muriate, 

 or chlorite of potash, but at a much lower temperature. 



3. The deflagration with nitrate of potash, and also with 

 chlorite of potash, was produced, in a suitable glass vessel, 

 to collect the compounded gas ; which was received into lime 

 water, and found to be charcoal acid. 



4. A little of the black powder was very easily ignited upon 

 a plate of platina, and was speedily burnt off^ smelling like 

 burning animal matter, and leaving a minute residue, some- 

 times of reddish powder and at other times of white. 



5. The powder was ignited in a green glass tube closed at 

 one end, and kept red hot from ten to fifteen minutes, the 

 open extremity being slightly stopt with a clay lute to prevent 

 the admission of air. A white vapour with water was dis- 

 charged, and a minute portion of animal empyreumatic oil was 

 condensed in the upper part of the tube. There remained 

 on cooling, a fine black powder, which in diflerent trials lost 

 y to ^ ; /. e. about r^ to -5^ of the original weight of the 

 substance. 



MDCCCXIII. Z 



