47 s 



A DESCRIPTION OF 



clear deep fiery red * : the fpirituous it alio deepens, but in a iefs degree* Sai 

 Martis changes the watery folution into a good durable ink. 



These are, I think, proofs, that a very fmall proportion of refin is prefent 

 in this fubftance: in this it differs efientially from the gum refin called Kino y 

 or Gummi rukrum ejirhigens, which the Edinburgh college has taken in- 

 to their materia medica (I have ufed the recent gum in making my experi- 

 ments* wliich may make fome difference) but as this can be moll perfectly 

 cdiffolved m waXry menftrua, it ,may prove of ufe, where a fpirituous folution 

 of the former (being the moll complete) cannot be fo properly adminiflcred, 

 confequently it may prove a valuable acquifition alfo. 



Infusions of the flowers, either frella or dried, dyed cotton cloth, previ- 

 oufly impregnated with a folution of alum, or alum and tartar, of a moll beauti- 

 ful bright yellow, which was more or lefs deep according to the llrength of 

 the infulion .: a little alkali added to the infufion changes it to a deep reddifh 

 orange ; it then dyed unprepared cotton cloth of the fame colour, which the 

 leafl acid changes to a yellow or lemon : thefe beautiful colours I have not 

 been able to render perfectly permanent. 



Amongst numberlefs experiments, I expreiTed a quantity of the juice of 

 the frefri flowers, which was diluted with alum water, and rendered perfectly 

 clear by depuration: it was then evaporated by the heat of the fun, into a 

 foft extract ; this proves a brighter water colour than any gamboge I have 

 met with; it is one year iince I firft ufed -it, and it remains bright. 



* With an alkalized decoction of this gum, I tried to dye cotton cloth prepared with alum, with fnpar 

 af lead, and with a folution of tin in ejua regsa, but the reds produced thereby were bad : that where aluca 

 was employed^ was the befi. 



