General Meeting, March 5th, 1878. 
Dr. R. Angus Smith, F.R.S., &c., Vice-President, in the 
Chair. 
Mr. Andrew Fairgrieve, of 4, Chester Street, Chorlton- 
on- Medlock, was elected an Ordinary Member of the 
Society. 
Ordinary Meeting, March 5th, 1878. 
Dr. R. Angus Smith, F.R.S., &c., Vice-President, in the 
Chair. 
“On the decomposition of Ultramarine by Carbonic 
Acid,” by Mr. S. SuGiURA (Student in the Chemical 
Laboratory of the Owens College). Communicated by 
Professor Roscoe, F.R.S., &c. 
It has been proposed to employ ultramarine for the detec- 
tion of free hydrochloric acid in presence of carbonic acid, 
on the ground that it is not acted upon by the latter, while 
the former easily attacks it.* In making some experiments in 
connection with this subject, I found however that carbonic 
acid itself decomposes ultramarine, as the following experi- 
ments will show. 
A glass cylinder about a foot in height and an inch in 
diameter was filled with distilled water, and carbon dioxide 
evolved from sulphuric and sodium bicarbonate or hydro- 
chloric acid and calcspar, was allowed to bubble up through 
* H. Muller, Che m. Soc. Jour., N. S., viii. 38. 
Proceedings— -Lit. & Phil. Soc. — Vol. XVII. — No. 9.— -Session 1877-8. 
