Geology and Mineralogy. 329 



ogy of the Paleozoic era. The book will contain a glossary and 

 also an index of the genera, and is expected to be ready for 

 delivery by November. It is to be published by the author. 



3. Note on the composition of Uraninite; by W. F. Hille- 

 brand (Communicated). — In the course of an examination of 

 uraninite which began with a specimen from Glastonbury, Conn., 

 and which has since been extended to specimens from every 

 available locality in this country and Europe, it was noticed that 

 on treatment of uraninite with an acid — sulphuric, hydrofluoric, 

 or hydrochloric, — a gas was invariably liberated in rather con- 

 siderable quantity so long as any of the mineral was yet unde- 

 composed, the time required varying very greatly with specimens 

 from different localities. The quantity of this gas given off has 

 been found to be from one to two per cent of the weight of the 

 mineral, and careful spectroscopic as well as eudiometric tests 

 indicate that it is nothing else than nitrogen. As to the reaction 

 by which this gas is given off or the manner in which it is 

 combined in the mineral, no clue has yet been discovered. It is 

 only in part driven off by ignition in air, and the portion retained 

 seems to bear a direct relation to the amount of N0 2 still in the 

 ignited product. Pending further investigation looking to the 

 clearing up of these interesting points and to the settlement of 

 the composition of uraninite in general, regarding which in other 

 respects as well as the above, my results are widely at variance 

 with those of Comstock, Blomstrand, and Lorenzen, this prelimi- 

 nary notice is now made public. It may be added that no uran- 

 inite from any American or European locality from which 

 specimens were obtainable except Bohemia has failed to show a 

 considerable percentage of thoria or (in one case) zirconia. 



Laboratory of the U. S. G-eol. Survey "Washington, D. C, Sept. llth, 1S89. 



4. Minerals from Franklin, N. J. — Dr. G. A. Koenig has 

 recently described the occurrence of chloanthite at the Trotter 

 mine, Franklin, N. J. ; it is chiefly massive, but crystals of 

 octahedral habit have also been observed. An amorphous min- 

 eral of a green color occurring as a crust or filling cavities in 

 fluorite has proved to be a hydrous silicate of nickel and zinc (ZnO 

 4 # 00 p. c.) allied to garnierite, giving the formula (Ni, Zn, Fe) 

 Si0 3 + l-g-H 2 0. This is named De Saulesite after Major A. B. 

 de Saules, manager of the Trotter miue. An analysis is also 

 given of a manganesian variety of willemite, (ZnO 60'61, MnO 

 10*04), to which the name of tephrowillemite is attached. — 

 Proc. Acad. Sci. Philad., p. 184, 1889. 



III. Miscellaneous Scientific Intelligence. 



1. Parallaxes of the fixed Stars. — In the Astronomische JSfach- 

 richten Nos. 2915-6 Dr. Oudemans gives the results of the deter- 

 minations of stellar parallax by astronomers during the last 60 

 years, being a Jubilee memoir on the 50th anniversary of the 



