270 Scientific Intelligence. 
mixed with 852 nome of cme ev and 78 of peroxyd of iron. The 
whole is then heated t w redness in a muffle cale cining furnace, the 
muffle of which is eantveltid | with an exhausting apparatus, by means 0 
which air dried by passing over lime is brought in contact with the 
mixture. The temperature of this should be kept so low that no per- 
chlorid of iron is sublimed. The mixture is carefully are from time 
to time, and the whole of the chlorine is thus obtain a gaseous 
state, mixed with pont but available for the crore of bleach- 
ing salts and for other purposes. The mufile now w contains a mixture 
plete. This mixture is ground with 144 parts of coal and heated to 
n in a reverberatory furnace, the hearth “ which is made of ground 
quick-lime mixed with a — basic slag or glass, and saturated with 
sulphuret of sodium by means of an aie of sulphate e of soda and 
coal melted upon its iaciion The fused mass after cooling is treated 
with water, and yields a residue of sulphuret of iron, and a solution of 
caustic soda saga iy ae by a ortion of suspended or pac lved 
action of the air, by which it is soon converted into sulphate of iron. 
This is removed by solution from the Sides of peroxyd of iron, n, and 
we have again yo two substances necessary for the denen eee of a 
new portion of sea-salt. 
, Mr. Macfarlane 
employs, in eeceak with the chlorine evolved . the method just 
Gexsiton the sulphurous acid obtained by burning sulphur or by cal- 
cining iron pyrites. The two gases being mixed in equivalent propor 
tions, and passed with a jet of steam through a condenser ed with 
coke, yield sulphuric and chlorhydric acids, in accordance with the 
equation, SO REP Tees +HCl. The mixed acids are se 
y distillation 
eons proposed by Mr. Macfarlane for the manufacture of 
aoa onsists in calcining a mixture of one passe cneh 
fou 
rc acid i is wat Bt Sole, st caus We ane cie : 
