702 



SCIENCE. 



[N. S. Vol. V. No. 122. 



Petrological Sketches. The rocks of the region 

 belong to three periods of activity: (1) the leu- 

 citic characterized by leucites and leucite-teph- 

 rites, (2) the trachytic and (3) the basaltic. 

 Among the rocks of the first period is a biotite- 

 vulsinite, a rock intermediate between the 

 trachytes and audesites. The silica is lower 

 than in the vulsinites, the lime, iron and mag- 

 nesia very much higher and the alkalies con- 

 siderably lower. Chemically the rock is almost 

 identical with ciminite, but in deference to the 

 present mineralogical classification of rocks it 

 is put with the vulsinites. 



Are the Bowlder Clays of the Great Plains 

 marine ? is asked by Dr. George M. Dawson, 

 and as a reason for the question he enumerates 

 several species of foraminifera, in part modern 

 forms, determined from the Canadian bowlder 

 clays by Mr. Joseph Wright. 



The Beauxite deposits of Arkansas are de- 

 scribed by Professor John C. Branner. The 

 beauxite deposits were discovered by the recent 

 Geological Survey of that State and are of fer- 

 ruginous, earthy and kaolin-like varieties with 

 pisolitic structure. In age they probably belong 

 to the Tertiary. They appear to have been 

 laid down in water near the shore and, in part 

 at least, to have been uncovered at low tide or 

 broken up by storm waves, rolled, and finally 

 left at or near where the material had originally 

 lain. In the opinion of Professor Branner, be- 

 fore the eruptive syenites had cooled they were 

 sunk beneath the Tertiary sea, and either by 

 the contact of the sea water or the issuing of 

 springs, whose waters had been in contact with 

 the hot syenites, the aluminous materials were 

 segregated as pisolite and sank near where they 

 were formed. The beds have not been devel- 

 oped, though they could be used to advantage 

 as a refractory material in the manufacture of 

 iron and steel. The paper includes a consider- 

 able bibliography. 



H. F. B. 



SOCIETIES AND ACADEMIES. 



NEW YORK ACADEMY OF SCIENCES — SECTION OF 



GEOLOGY, APRIL 19, 1897. 



The evening of the monthly meeting of the 

 Section was devoted to a reception, by the 

 whole Academy, to Sir Archibald Geikie, Direc- 



tor-General of H. M. Geological Survey of 

 Great Britain, who had just returned to this 

 country for a brief visit after an absence of 

 eighteen years. After an informal reception 

 the meeting was called to order and addressed 

 briefly by the President of the Academy, Pro- 

 fessor J. J. Stevenson, who extended a most 

 hearty welcome from the scientists of New York 

 to the guest of the evening. Professor Steven- 

 son was followed by Professor J. F. Kemp, the 

 Chairman of the Section, who reviewed in a 

 few words the greater contributions of Sir 

 Archibald Geikie to the cause of geology. He 

 spoke of his early work in Scotland, in France 

 and in the western United States in the study 

 of vulcauism, and paid particular attention to 

 the work that had been done in Scotland on 

 the metamorphic rocks. Professor Kemp con- 

 cluded with a tribute to Sir Archibald as a nat- 

 uralist, and spoke of the superior quality of 

 work that is given the world by the man who 

 is in love with nature and finds in the solitude 

 of the wildness of nature his greatest company 

 and inspiration. 



The next speaker was the Secretary of the 

 Section, who spoke particularly of the work of 

 Sir Archibald Geikie as looked at from the 

 standpoint of the teacher and physiographer. 

 He reviewed hastily the character and quality 

 of Geikie' s Text-book and Class-book of Geol- 

 ogy, and spoke more especially of the example 

 this distinguished geologist has set in physi- 

 ography in the masterly analysis of the physical 

 features of Scotland given in his Scenery of 

 Scotland. 



The last address of welcome was given by 

 Professor Angelo Heilprin, of Philadelphia, who 

 spoke as a traveler and contrasted the knowl- 

 edge of the geology of the world now with our 

 knowledge at the time of Humboldt. He spoke 

 of how much we owed to the guest we were 

 welcoming for his work in bringing together- 

 the shreds of knowledge from all parts of the 

 world and in building up a great mass of geo- 

 logical information, which is a vast help to all 

 workers in geology and a stimulus to all. 



In reply Sir Archibald Geikie expressed his 

 thanks to the Academy for the very cordial 

 reception that had been tendered him in New 

 York. He contrasted the appearance of the 



