of charcoal and hydrogen. 161 
probably, therefore, either a mixture of olefiant gas with a 
heavier and more combustible gas or vapour, or a new gas 
sui generis , consisting of hydrogen and charcoal, in propor- 
tions that remain to be determined. 
Manchester, January 1821 . 
From the Press of 
IV. BULMER ST Co. 
Cleveland-row, St. James's, 
London. 
