IS15.] O/i the •colouring Matter ejected hj the Cuttle Fish. 417 



some flakes fell, leaving the liquor nearly transparent and colour- 

 less. Acetic acid produced no coagulation, and this acid, more- 

 over, prevented its coagulation by heat; hence it contained 

 albumen. Muriate of barytes produced a very copious white 

 precipitate. 



From experiments, which it would be unnecessary to detail here, 

 it was found that 1000 parts contained 



Water 977 



Albumen 2'6 



Sul)stances soluble in alcohol 16*6 



Substances soluble in water, chiefly sulphate of~) „^ 

 soda? and other salts. Also sugar of milk . . j 



1000-0 ' 



The principles soluble in alcohol were of a brown colour, and 

 seemed to consist in part of the lactates, &c , as usual ; but chiefly 

 of a peculiar substance quite diflerent from every other that I had 

 examined, and which has a considerable resemblance in its sensible 

 properties to the CKternal brown parts of roasted veal. 



My want of leisure prevented me from examining this fluid 

 more particularly. It may not, however, be improper to observe, 

 that the liquor amnii described by Vauquelin and Buniva differed 

 very considerably from the above in its sensible qualities, as well as 

 in its chemical ones. This dissimilarity probably arose from the 

 different circumstances under which it was obtained, theirs, most 

 likely, having been procured at the full period of gestation. These 

 chemists, however, describe a principle obtained by them, soluble 

 in alcohol, and having peculiar properties, which, though it ap- 

 j)eared to resemble in some respects that above mentioned, dift'ered 

 from it in others. Sec Ann. de Chim. N° 99. Johnson's Animal 

 Chemistry, vol. i. p. 274. Dr. Thomson's System of Chenaistry, 

 vol. v. 



Article III. 



On the colouring Matter, or Ink, ejected by the Cuttle Fish. 



By Dr. Prout. 



Til K substance, of which an account is given below, was sent 

 me in the original cyst in a perfectly dry state. The following 

 were its properties. 



It was hard and brittle. Fracture imperfectly concholdal. 

 When solid, of a brownish black colour, and exhilnting a slight 

 pavonine lustre, on exposure to a strong light. In a state of 

 jMiwdcr, of a beautiful velvet black. No smell. Taste rather 

 fcaltibh. Sp, gr. in powder, I'GW. 



A. 25 grains were digested in distilled water, and allowed tQ 

 Vol. V. JSi» VI. 2 D 



