THE 



PHILOSOPHICAL TRANSACTIONS 



OP THE 



ROYAL SOCIETY OF LONDON; 



ABRIDGED. 



An easy Method of procuring the Folatile Acid of Sulphur. By Ephraim 

 Rinhold Seehl. N°472, p. 1. Vol. XLIII. 



JAxR. S. here describes two modes of obtaining what he terms volatile acid of 

 sulphur, which is the sulphurous acid of later chemical writers. 



His 1 st method is as follows : Take 1 lb. of the flowers of brimstone, and 

 5 lb. of dry fixed alkaline salt ; grind them together, and put the mixture into an 

 iron pot ; add gradually, a little water, so as first to dissolve the fixed alkali ; then 

 gradually dispose the whole to boil, the better to dissolve the sulphur: when these 

 have boiled for -j- of an hour, add more water by degrees ; and, when the sulphur 

 appears to be dissolved, filtre the solution; evaporate it to perfect dryness in an 

 iron pot, till it almost begins to melt; then take out the dry powder when coolj 

 put it into a tubulated retort; which being placed in a sand-heat, and a receiver 

 luted on, pour in at the tube, by degrees, 2 lb. of rectified oil of vitriol; and 

 immediately secure the tube with a stopple of chalk, and luting: then give a 

 gradual fire for some hours, till all the volatile spirit of sulphur is come over; after 

 which, let the fire go out; take off the receiver, and carefully pour the liquor in 

 to a glass phial, to be stopped with a glass stopper. The volatile spirit, thus pro- 

 cured, will be about 12 oz. in weight, and appear tolerably limpid, smell ex- 

 tremely quick, pungent, and gassy or sulphureous, almost like the gas sulphuris, 

 prove strongly acid to the taste, and in all other experiments; so that it may be 

 used in the way of a general acid; being perhaps the best, in all respects, that is 

 hitherto known, except the following. 



Process 1. — Take 1 lb. of the flowers of brimstone, 44.1b. of fixed alkaline salt; 

 grind and mix them well together ; put the powder into an iron pot set over the 



VOL. IX. B 



