Scientific Intelligence — Mineralogy. 383 



19. Allanite^ Cerine, and Orthite. — Scheerer, who formerly proved 

 that these three substances could be brought under the same chemi- 

 cal formula, has now rendered it probable that they also have the 

 same crystallographic form. — (^Rammelsberg' s Zweites Supplement, 

 p. 9. From Poggend. Ann., Vol. Ixi., p. 645). 



20. Anatase, Brookite, and Rutile. — Professor Henry Rose, in 

 the course of his recent investigations on Titanic Acid, has fully 

 cleared up the chemical nature of anatase, which had been pre- 

 viously doubtful (Poggend. Ann., Ixi., 516). Anatase is pure titanio 

 acid, just like Brookite and Rutile. When exposed to heat, by which 

 its specific gravity is not altered, or, to the action of solvents, it pre- 

 sents no phenomena different from those exhibited by the two mine- 

 rals just mentioned, and the quantity of iron contained in it is still 

 less than the amount in those two substances (the Anatase of 

 Brazil contains 0*25 per cent, oxido of iron). Rutile, Brookite, 

 and Anatase, are the first decided example of atrimorphism, in whose 

 members the titanic acid is distinguished by a different specific 

 gravity. On being exposed to heat, however, the Anatase acquires 

 the specific gravity of Brookite, and afterwards that of Rutile, and 

 Brookite itself acquires the specific gravity of Rutile. It thus ap- 

 pears that, by the action of heat, the one substance is converted into 

 the other ; and precisely the same phenomena occur in the case of 

 artificially prepared titanic acid. According to Damour (Ann. Chim. 

 Phys. iii. Ser. x) the composition of Brazilian Anatase is the 

 following: Titanic acid 98*36; oxide of iron I'll; oxide of tin 

 0.20 = 99*67. — (^Rammelsberg'^s Zweites Supplement zu demHand- 

 worterbuch des Chemischen Theils der Mineralogie, p. 13.) 



21. Occurrence of Diaspore at Schemnitz, — In a paper published 

 in Poggendorff 's Annals (Vol. Ixi., p. 307.), Mr Haidinger men- 

 tions that Diaspore has been found in a peculiar position in the 

 Kronprinz-Ferdinand-Evbstollen, near the Dillner Georgi-Erb' 

 stollen at Schemnitz. The crystals and fibrous portions are met 

 with in a matrix of figure stone or agalmatolite, which occurs in a 

 decomposed secondary rock, interposed between dolomite and lime- 

 stone, and associated with iron-pyrites. A diorite porphyry incloses 

 the whole on both sides. The specific gravity of the Schemnitz 

 diaspore is 3*303 ; and the hardness 6. The crystals belong to the 

 Orthotype system. Mr Haidinger gives some interesting details 

 regarding the dichroism and trichroism of this mineral. He seems 

 to think that the Schemnitz diaspore may prove a distinct species. 



22. Yttro-Cerite. — This rare mineral has been found by Mr 

 Alger associated with Brucite, in masses of rolled limestone from 

 the town of Amity, Orange county. New York. 



23. Dysluite identical with Automolite. — Mr Alger states, that 

 from recent observations of the New Jersey specimens, he is satis- 

 fied there is no reason for any longer considering the two minerals 

 distinct. The characteristic differences heretofore insisted on — ' 



