216 



SCIENCE. 



[N. S. Vol. XXI. Xo. 528. 



A. B. Coble: 'Some applications of a theorem 

 ill tlie theory of forms.' 



I,. E. Dickson: ' Tlie group of a tactical con- 

 figuration.' 



T. S. FiSKE: Presidential address, 'Mathe- 

 matical progress in America." 



JIaurice Frechet: ' Sur les operations 

 lin^aires (deuxifeme note).' 



F. MoRLEY: 'On an inversive relation between 

 five points of a plane.' 



J. E. Wright: 'Application of the theory of 

 continuous groups to a certain dili'crential equa- 

 tion.' 



Edward Kasner: 'Geometry of point cor- 

 respondences: osculating homographies.' 



C. H. SiSAM : ' On septic scrolls.' 



E. V. Huntington : ' Note on definitions of 

 groups, abelian groups, and fields.' 



E. V. Huntington : ' A set of postulates for 

 ordinary complex algebra.' 



Burke Smith: 'On the deformation of sur- 

 faces of translation.' 



L. E. Dickson: 'A general theorem on alge- 

 braic numbers.' 



-A. B. Coble: 'The similar projective groups 

 of a cubic space curve and a quadric surface.' 



E. H. Moore: 'On a definition of abstract 

 groups.' 



The Chicago Section of the society met 

 at Chicago, on December 30-31. The next 

 meeting of the society will be held on 

 February 25. The San Francisco Section 

 will meet on the same date. 



F. X. Cole, 

 ; Secretary. 



THE (lEOLOGICAL SOCIETY OF AMERICA. 



The seventeenth annual meeting of the 

 Geological Society of America was held at 

 the University of Pennsylvania, Philadel- 

 phia, December 29-31, 1904, under the 

 presidency of Professor John C. Branner, 

 of Stanford University. Sixty-one papers, 

 divided among eight branches of the sci- 

 ence, were presented for reading, and about 

 one hundred members of the society were 

 in attendance, making the convention one 

 of the largest in its history. The report of 

 the council for the year 1904 shows that in 

 all respects the affairs of the society are in 



a highly satisfactory condition. The net ac- 

 tive membership of the society was reported 

 as being 259, and 15 new members were 

 elected at the Philadelphia meeting. Dur- 

 ing the past year, five members have been 

 removed by death, Professor C. E. Beecher, 

 J. B. Hatcher, Henry McCalley, W. H. 

 Pettee and Charles Schaffer. ]\Iemorials 

 of these members were read at the first ses- 

 sion of the Philadelphia meeting. 



The report of the treasurer showed that 

 the society had a balance in the treasury, 

 December 1, 1904, of $1,973.68 and in- 

 vested funds amounting to $8,300. The 

 volume of the Bulletin of the society com- 

 prises 636 pages of text, with 75 illustra- 

 tions, the articles being divided among nine 

 branches of the science, of which strati- 

 graphic geology occupies about one half. 

 The library of the society, which is de- 

 posited with the Case School of Applied 

 Science in Cleveland, now comprises some 

 2,600 numbers, of which 1,400 are bound 

 volumes. 



Professor Branner chose as the subject 

 of his presidential address, ' Geological and 

 Geographical Studies on the Northeast 

 Coast of Brazil,' and illustrated his paper 

 by means of numerous photographs and 

 charts. The most peculiar feature of this 

 coast is the series of hardened sandspits 

 occurring at the mouths of most of the 

 rivers. These spits consist of quartzose 

 sand which has been cemented together into 

 a hard solid rock by means of calcium car- 

 bonate brought down in solution by the 

 rivers and precipitated by contact with the 

 waters of the ocean, which here possess a 

 high degree of salinity. This hardening 

 extends to a depth of several feet and, in 

 many instances, has been of great economic 

 importance through the formation thereby 

 of natural breakwaters, forming safe har- 

 bors, as at Pernambuco. The spits contain 

 many fossils, all of which are of living spe- 

 cies. A second coast feature of importance 



