620 



SCIENCE. 



|X. S. Vol. XIX. No. 485. 



The mineral celestite does not occur in 

 veins or cavities, but disseminated through 

 the rock, the manner of dissemination differing 

 somewhat in different sections; in some places 

 the crystals were not nearly so perfect as in 

 others, often collected in small circular spots. 

 The crystals have the usual combinations of 

 faces found in celestite as well as the specific 

 gravity and optical properties of this mineral. 



While the mineral was originally found near 

 Jamesville it has more recently been found 

 elsewhere and, the author believes, is of gen- 

 eral occurrence in the limestones of the Sa- 

 lina. In places where rocks containing the 

 celestite were exposed to the weather, the 

 mineral was dissolved, leaving cavities which 

 b"y their distinct outlines indicate the charac- 

 ter of the material which they had contained. 

 In some localities the crystals were large and 

 their impressions simulate the marks of chisel 

 blades of about three fourths of an inch in 

 width, occasionally single but often crossing 

 one another. 



In the rocks, where this mineral occurs in 

 circular particles, leaching gives rise to an 

 appearance as if the stone were worm-eaten, 

 and bearing a striking resemblance to the 

 ' vermicular limestone.' The ' vermicular 

 limestones ' have given geologists much trouble 

 as to a satisfactory explanation of their for- 

 mation. That sodium chloride was the ori- 

 ginal occupant of these cavities seems doubt- 

 ful. But celestite is soluble in water contain- 

 ing small quantities of sodium, calcium or 

 mag-nesium-chloride. Analyses of the brines 

 from the different salt-producing sections of 

 the state easily proves the presence of these 

 chlorides. With these facts in mind and know- 

 ing that the dissemination of celestite through 

 the rock is not unlike that which would be 

 necessary to form cavities as found in the 

 vermicular and that when such a rock has 

 been leached, the appearance of the resulting 

 rock is like that of the vermicular, the con- 

 clusion seems unavoidable that these many 

 cavities now empty in the vermicular must 

 have once contained a mineral of the char- 

 acter of celestite and that by the action of 

 the agencies mentioned above the same was 



dissolved, leaving nothing but the so-called 

 cells to show its former presence. 



J. E. KlEIvWOOD, 



Corresponding Secretary. 



THE SCIENCE CLUB OF THE UNIVERSITY OF 

 WISCONSIN. 



The fifth meeting of the club for 1903^ 

 was held February 23, in the physical lecture 

 room of Science Hall. The club had for its 

 guest the local section of the American 

 Electrochemical Society, this being the first 

 meeting of the local section. The papers 

 were presented by members of the section. 

 The first paper, by C. F. Burgess, on ' Electro- 

 lytic Iron,' was illustrated by specimens and 

 products of pure iron recently obtained by 

 him by electrolysis. One specimen of ex- 

 tremely pure material weighted twenty-one 

 pounds. 



The second paper, by Oliver W. Brown, on 

 ' The Electric Eurnace,' was a general de- 

 scription of the recent advances made in 

 electric furnace work. 



The third paper, by V. Lenher, on the 

 ' Solubility of Gold,' was illustrated by ex- 

 periments and dealt with some recent work 

 of the author. 



Victor Lenher, 



Secretary. 



DISCUSSION AND CORRESPONDENCE. 

 convocation weee. 



To THE Editor of Science: Having at- 

 tended a majority of the meetings of the 

 American Association for the Advancement 

 of Science during the past fifteen years I may, 

 perhaps, be considered competent to contribute 

 some impressions in regard to recent tenden- 

 cies and the future development of the associa- 

 tion which they apparently indicate. 



It has always seemed to me that in any at- 

 tempt to solve a problem such as that of the 

 future policy of the association the proper 

 course to pursue is to study the causes which 

 have led up to existing conditions and from 

 these to try and anticipate what the inevitable 

 outcome is to be. Discussion of personal 

 likes or dislikes is profitless if these are mani- 

 festly at variance with the general course of 



