or Cow Tree of South America, 455 



which, from previous experiments, I had ascertained would 

 dissolve the waxy principle, or galactin. By this process 

 30*57 grains of galactin were dissolved, leaving a brown pow- 

 der weighing 7*43 grains. 



Cold water was poured on this residue, and dissolved 4*37 

 grains, yielding a solution precipitated by alcohol, becoming 

 viscid when evaporated, and having hardly any taste ; what 

 little it had was derived from traces of saline matters: it was 

 evidently gummy matter coloured slightly by extractive. The 

 residue, weighing 3*06 grains, was boiled in alcohol ; the solu- 

 tion gave a precipitate with perchloride of mercury and with 

 galls; this agrees entirely with the characters of gluten. 

 There yet remained a small quantity of a brown powder, which 

 was easily soluble in a weak solution of caustic potassa; this 

 proved to be vegetable albumen. It is very probable that in 

 the sap, these two last- mentioned substances were held in so- 

 lution by acetic acid, and that they were precipitated on its 

 evaporation. From these experiments the sap appears to 

 contain 



1. Water and acetic acid 62*00 



2. Galactin 30*57 



3. Gum and saline matter, 

 bably acetate of magnesia 



4. Gluten and albumen 3*06 



™> P ro -\ 4*37 

 >ia J 



100*00 

 When the aethereal solution of galactin was evaporated, and 

 the residue carefully fused to expel all adhering aether, pure 

 galactin was obtained ; its properties were as follows. It was 

 transparent, and of a pale yellow colour ; tough, adhering 

 strongly to the ringers, and drawing out between them into 

 threads, having a shining pearly lustre ; but at low tempera- 

 tures it became hard and brittle. It was fusible between 120° 

 and 130° Fahrenheit; when exposed to a heat of above 500°, 

 it boiled and was entirely volatilized, but I rather believe a 

 portion was decomposed, giving rise to the formation of a 

 highly combustible fluid; it was combustible like wax, burning 

 with a bright smoky flame. On the surface of boiling water 

 it floated like an oil, and was not sensibly altered, but a por- 

 tion was carried up in vapour with the steam ; when, how- 

 ever, the galactin was not perfectly dry, or contained any 

 moisture, it rendered the water turbid from the mechanical 

 suspension of small particles throughout it. It was not sa- 

 ponifiable by potassa or by ammonia ; when not dry, however, 

 it frothed up, and seemed to combine with a boiling solution 

 of potassa; on cooling, it separated unaltered. It was soluble 



