ee 
266 Scientific Intelligence. 
mitted, which passes over the surface of the melted mixture and car- 
ries off muriatic acid with more or less volatilized salt into the conden- 
sers. When the steam escaping from the cylinder ceases to contain 
any notable quantity of muriatic acid, the operation is discontinued and 
the charge is withdrawn. Its soluble salts are extracted by water, and 
arated from any undecomposed muriate by 
evaporation and crystallization. 
In this operation the heat should not be raised so high as to cause the 
decomposition by the steam of the sulphate of soda produced, or the 
sulphate of lime itself. 
Though 1 prefer in all the above described processes heating the 
steam highly before passing it upon the salt to be decomposed, yet the 
same effect will be produced whenever the steam and salt are in con- 
tact at the proper temperature for the respective decompositions, wheth- 
er they have both been previously heated, or one alone heated so highly 
as to be able to raise the other to the required temperature. As has 
been before stated, some of the salts are decomposable by steam at a 
much lower temperature than others, but with all the decomposition 
proceeds more rapidly in proportion as the heat is increased. 
I claim as my invention the decomposing the sulphates of baryta, 
strontia, lime and magnesia, and the muriates of baryta, strontia and 
lime, by exposing them at a high temperature to the action of a current 
of steam, for the purpose of obtaming the acids and the alkalies of 
these salts respectively. 
I also claim the decomposing the sulphates and muriates of potash 
and soda, for the purpose of obtaining the acids and the alkalies of 
these salts respectively, by exposing them at a high temperature to the 
action of @ current of steam, alumina or the other combining substan- 
ces being present. 
I also claim making aluminates of potash and soda by the action of 
a current of steam upon a mixture of alumina and the sulphate or mu- 
riate of potash or soda at a high red heat. 
I also claim the making sulphate of soda by the action of a current 
of steam upon the muriate of soda at a red heat, sulphate of lime be- 
ing present as described. 
Il. Minzeranocy anp Geoxocy. 
1, Samarskite—M. H. Rosz has shown that while minerals that 
present luminous phenomena when heated, have generally greater spe- 
cific gravity after heating than before, (as gadolinite,"orthite and alla- 
nite,) sama ite, on the contrary, has the reverse relation to heat. 
jae > 
actual weight. This fact accounts for t different specific gravit 
obtained by Hermann for the mineral designated jeri 
since proved to be samarskite. 
Rose has found, after several trials, that the luminous phenomena of 
dolinite and oxyd of chrome precipitated by ammonia, were always 
companied by a sudden disengagement of heat. This was shown 
