Chemistry and Physics. 393 
tion of the sodium salt, to isolate an oil boiling at 285°, which on 
oxidation is entirely converted into the yellow body, ‘and which 
has the formula C, ,H,,0Os, its a derivative bein 
stance lon "ago described by Reichenbach* siden the name 
cedriret. ‘The Siasietiod originally given of it i d is 
full and complete. at a body possessed perties so strik- 
to doubt it, owing to Reichenbach’s having dehetibed it as a pre- 
rer of fine red needles, and having obtained it from wood tar; 
w 
a ee 
a new repent — Kosin.—A new coloring sub- 
5. On 
stance, introduced into commerce ray the last summer under 
he name of Eosin, has been examined by Hormann. It has a 
due ee ca potassium bromide. Distilled cape fase pre: . 
afforded benzol. Its aqueous mga on treated wi 
acid, appeared as yellow bing) aving the composition C9 
r,0, ; a formula confirmed by the analysis of the barium salt, 
CaoH Br,BaO,. From these data ieee concluded that eosin 
ata obtained Gibseas tabaci in beautiful white needles, 
Eosin is therefore the phthaléin of dibrom-resorcin. Its synthesis 
was very easily accomplished by acting on an acetic solution of 
* Berzelius Jahresbericht, xv, 408. 
