460 



SCIENCE 



[N. S. Vol. XXXVII. No. 951 



BocTc Classifications in Three Dimensions: Alex- 

 ander N. WlNCHELL. 



Believing that tabular classifications are de- 

 sirable because of their simplicity, but that, as 

 previously devised, they are unnecessarily limited 

 in their presentation of mutual relationships, a 

 new classification of igneous rocks is presented 

 vrhich is in tabular form in three dimensions. It 

 is based largely upon the principles and work of 

 Eosenbuseh, but it diifers from his usage in vari- 

 ous important respects, so that responsibility for 

 it must lie with the author. 



Geo. F. Kay, 

 Secretary Section E 



SOCIETIES AND ACADEMIES 



THE AMERICAN MATHEMATICAL SOCIETY 



The one hundred and sixty-second regular 

 meeting of the society was held at Columbia 

 University on Saturday, February 22, extending 

 through the usual morning and afternoon sessions. 

 The attendance included thirty -eight members. 

 Ex-president H. S. White occupied the chair, be- 

 ing relieved by Professors E. W. Brown and 

 Frank Morley. Sixteen new members were ad 

 mitted: Professor E. P. Adams, Princeton Uni 

 versity; Dr. H. L. Agard, Williams College; Pro 

 fessor Fiske Allen, Kansas State Normal School 

 M. Farid Boulad, Egyptian State Railways; Pro 

 fessor J. A. Caparo, Notre Dame University 

 Mr. C. H. Clevenger, Kansas State Agricultural 

 College; Dr. A. L. Daniels, Jr., Yale University 

 Mr. W. Van N. Garretson, University of Mich 

 igan; Mr. G. M. Green, Columbia University 

 Mr. C. E. Love, University of Michigan; Dr, 

 Thomas Muir, Education Office, Capetown, S. A.; 

 Mr. J. A. Nyberg, University of Wisconsin; Dean 

 Marion EeUly, Bryn Mawr College; Professor B 

 L. Eemick, Kansas State Agricultural College 

 Professor W. V. Skiles, Georgia School of Tech 

 nology; Mr. J. N. Vedder, University of Illinois 

 Five applications for membership were received 



The society is about to publish the lectures de^ 

 livered at the Princeton colloquium in 1909 by 

 Professors G. A. Bliss and Edward Kasner. 



The following papers were read at this meeting: 



Harris Hancock : "A theorem in the analytic 

 geometry of numbers." 



B. H. Camp : ' ' The expression of a multiple 

 integral as a simple integral. ' ' 



G. M. Green: "Projective differential geometry 

 of triple systems of surfaces." 



C. A. Fischer: "A generalization of Volterra's 

 derivative of a function of a curve. ' ' 



L. B. Robinson: "Notes on the theory of sys- 

 tems of partial differential equations." 



Oswald Veblen and J. W. Alexander, II. : 

 ' ' Manifolds of n dimensions. ' ' 



R. G. D. Richardson : ' ' Oscillation theorems for 

 linear homogeneous self-adjoint partial differen- 

 tial equations with one parameter. ' ' 



L. P. Copeland : ' ' Concerning the theory of in- 

 variants of plane m-lines. " 



T. H. Gronwall: "On the summability of Four- 

 ier's series." 



T. H. Gronwall : ' ' On Lebesgue 's constants in 

 the theory of Fourier 's series. ' ' 



T. H. Gronwall : ' ' On the degree of convergence 

 of Laplace 's series. ' ' 



N. J. Lennes : ' ' Note on Lebesgue and Pier- 

 pout integrals. ' ' 



N. J. Lennes: "Finite sets and the foundations 

 of arithmetic. ' ' 



H. Bateman: "The expression of the equation 

 of the general quartic curve in the form A/xx" + 

 B/yy' + C/ze' = 0." 



H. Bateman : ' ' Sonin 's polynomials and their 

 relation to other functions. ' ' 



Dunham Jackson : ' ' On the accuracy of trig- 

 onometric interpolation. ' ' 



C. E. Wilder : "On the degree of approxima- 

 tion to discontinuous functions by trigonometric 

 sums." 



Edward Kasner: "Systems of curves connected 

 with equUong transformations." 



The next regular meeting of the society will be 

 held at Columbia University on Saturday, April 

 26. The Chicago Section will meet at the Univer- 

 sity of Chicago on Friday and Saturday, March 

 21-22. The San Francisco Section meets at Stan- 

 ford University on Saturday, April 12. 



F. N. Cole, 

 Secretary 



the academy op science op ST. LOUIS 



At a recent meeting of the academy held on 

 February 17, 1913, Professor Nipher presented an 

 abstract of a paper soon to be published by the 

 academy, entitled "A Local Magnetic Storm." 



The phenomena were produced by means of two 

 steel magnets, placed on opposite sides of a mag- 

 netic needle, as in the Gaussian method of deflec- 

 tion. The needle was completely enclosed in a 

 copper cylinder. Its motion was observed through 

 a small glass window, covered with wire gauze, by 



