897 
presence of the silicate and the thermo-element. Finally in no case 
ihe infection of the used thermo-elements was controlled, neither 
were the obtained data reduced on the nitrogen-gasthermometer of 
Washington. A short review of the data given in literature will 
soon persuade the reader of the facts mentioned. 
§ 2. According to STEIN) a molten mass of the composition 
SrSiV, erystallises at 1287° C. He prepared the compound by melt- 
ing together the oxides, carbonates and hydroxides with silica in 
tubes of carbon, while in his measurements the porcelain protecting 
tube of the thermo-element was placed in most cases quite bare 
into the molten mass. As he mentions, the colour of his products 
was indeed more or less dark-gray, as a consequence of the admixed 
carbon. The specific gravity should be 3,89 or 3,91; no glass was 
obtained. According to Warracu®) however the solidifying-point of 
SrSi0, should be 1528° C.; he worked in an analogous way, and 
says, that the solidified substances were always greatly contaminated 
by admixed carbon, their colour being thus black or bluish-black. 
The crystallised product should be very analogous to calcium-meta- 
silicate: very strongly birefringent, obliquely or normally extinguishing 
monoclinic prisms. Evidently this analogy must be present between 
this compound and the pseudo-rwollastonite, the common solidifying- 
product of the molten calcium-metasilicate. The last modification 
being typically pseudo-hexagonal, the same should be the case with 
SrSiO,; however, this is nowhere mentioned by the author, and 
thus needs more detailed study. 
According to Straw BaSiO, erystallises at 1368° C.; the product 
should possess a specific gravity of 3.77, and also be obtained in 
the form of a glass with a specifie weight of 3.74. In this case also 
all experiments were made in carbon-tubes, and all solidifying-points 
were determined by means of coo/img-curves. 
According to LeBepew *) the solidifying-temperature is: 1488° C. ; 
the method used was the same. The product is according to this 
author monoclinic, and isomorphous with CaSvO,; but it is.not said 
with which modification of it. 
On the contrary Warrace finds 1490° C. for the solidifying-point, 
and in contrast to Stxrm’s experience, only a single crystalline 
modification, instead of two different ones. 
1) G. Srern, Zeits. f. Anorg. Chem 55. 159. 163. (1907). 
2) R. C. WALLACE, Zeits. f. Anorg. Chem., 63, 9. 10. 11. (1909). 
3) P. LeBepew, Zeits. f. Anorg. Chemie, 70, 501, 317 (1911). 
58* 
