15 
M. Rose on the Oxide of Titanium. 
gene contains potash ; and that the analcime contains two pro- 
portions of water, whilst the amphigene is anhydrous. The 
chemical composition of analcime will then be NS*-j- 
The two minerals affect the same form. M. Rose asksj if the 
soda, combined with these two proportions of water, may not 
be isomorphous with the anhydrous potash 
This skilful young chemist has also studied the nature and 
composition of the Oxide (rf Titanium^ which has so long been 
little known. M. Rose entertained the happy thought of re- 
ducing the oxide of titanium to the state of sulphuret, by means 
of the vapours of the sulphuret of carbon, which he made to 
pass through an incandescent porcelain tube, containing the oxide 
of titanium. The sulphuret of titanium thus obtained, is a 
greyish-yellow mass bordering on green, which, by the slightest 
touch, takes a metallic lustre resembling the magnetic sulphu- 
retted iron. When this sulphuret is heated with caustic potash, 
it oxidates, and there results from it a hydrosulphate and a 
titanate of potash, without excess of sulphur, and, consequent- 
ly, the sulphuret of this metal contains the same number of 
atoms of sulphur as there are atoms of oxigen in the oxide. By 
exposing it to the fire, it burns with a blue flame, and is con- 
verted by degrees into an oxide of titanium. The difference 
between the weight of the sulphuret and that of the oxide, in- 
dicates the quantity of oxigen which it contains. The oxide of 
titanium contains 33.93 hundredths of its weight of oxigen. It 
does not possess any of the characters of a salifiable base. The ni- 
trate and the muriate of titanium, which chemists have described, 
are merely salts with a base of potash and soda. The oxide of 
titanium is precipitated from its solutions in a great part by 
ebullition. The insoluble combinations which it appears to form 
with the Sulphuric, Arsenic, Phosphoric, and Oxalic Acids, are 
not salts. The oxide in them contains at least four times as 
much oxigen as the acid, and sometimes even more. The oxide 
of titanium combines with water, and reddens vegetable blues. 
At a high temperature it drives off the carbonic acid, and com- 
bines with the bases. We ought, therefore;, to change its name 
into Titanic Acid. The titanates of potash and soda may be 
obtained by melting the titanic acid with the carbonates of pot- 
