350 General Notes. 
baryto-celestite, accompanying the wagnerite at Werfen in Salzburg, 
to consist of 84.8 per cent. of barium sulphate and 15.05 per cent. 
of strontium sulphate. Like Professor Chester,' they regard the 
substance as an isomorphous mixture rather than as a definite 
compound. 
MISCELLANEOUS.— Wollastonite is most frequently found in 
nature as a newly formed mineral in metamorphic rocks. It has 
also been detected as a primary constituent in eruptive rocks. Man 
experimenters have succeeded in obtaining the mineral artificially 
and with a aa eai refractive index. His mode of operation was 
to warm a little 
1 American Naturalist, 1887, p. 852. 
2 Neues Jahrb. f. Min., etc., 1886, i., p. 119. 
3 Mineralogische und Petrographische Notizen, Bonn. p. 9. 
4 Comptes Rendus, cv., 1887, p. 1265. 
