May 20, 1898.] 



SCIENCR 



719 



tion of special regular reticulations on a closed 

 surface.' 



5. Professor E. O. Lovett : ' Infinitesimal 

 transformations of concentric conies.' 



6. Professor E. O. Lovett : ' Note on in- 

 finitesimal projective transformations.' 



7. Professor Maxime Bocher : ' Note on 

 Poisson's integral.' 



Afternoon Session. 



8. Mr. W. M. Strong : ' On the necessity of 

 continuity in Euclid's geometry.' 



9. Professor A. G. Webster : ' Note on 

 Stokes' theorem in curvilinear coordinates.' 



10. Professor E. B. Van Vleck : ' On the 

 polynomial of Stieltjes.' 



11. Mr. G. p. Starkweather : 'A solution 

 of the biquadratic by binomial resolvents.' 



12. Dr. G. a. Miller : ' On the supposed 

 five-fold transitive function of 24 elements and 

 19 !-^48 values.' 



13. Dr. G. a. Miller : ' On the Hamilton 

 groups. ' 



The Summer Meeting of the Society will be 

 held at the Institute of Technology, Boston, 

 Mass., on Friday and Saturday, August 19th 

 and 20th, in affiliation with the American 

 Association for the Advancement of Science. A 

 colloquium will be held in connection with the 

 meeting, two courses of lectures being offered 

 by Professor W. F. Osgood, of Harvard Uni- 

 versity, and Professor A. G. Webster, of Clark 

 University. ^ ^_ ^^^^_ 



Secretary. 

 the philosophical society of WASHINGTON. 



The 484th meeting of the Philosophical So- 

 ciety was held at the Cosmos Club, at 8. p. m., 

 April 30th. The first paper was by Mr. William 

 Eimbeck on ' Terrestrial Refraction,' as related 

 to the determination of heights by trigonometric 

 processes. 



Conceiving refraction to depend solely upon 

 the density of the atmosphere, he showed that 

 it varies not only with the hour of the day, but 

 likewise with the seasons of the year and the 

 heights above the sea, etc. Also, that the di- 

 minution of the refraction with heights as ex- 

 hibited by the coefficients for the various levels 

 of elevation must not be neglected, as is custo- 



mary in the' computation of heights from zenith 

 measures, if the utmost attainable precision is 

 sought. On account of the decrease of atmos- 

 pheric density, the refraction at a higher station 

 is necessarily always less than at a lower sta- 

 tion. 



This is a condition, the effect of which is not 

 eliminated by simultaneous measures of recip- 

 rocal zenith distances. 



The second paper was by E. D. Preston on 

 ' Kecent Progress in Geodesy.' After a brief his- 

 torical review of what has been done thus far in 

 determining the size and shape of the earth, at- 

 tention was called to some recent measure- 

 ments of parallel arcs. It was pointed out that 

 both in Europe and America the above meas- 

 ures indicate a smaller radius of curvature than 

 that determined by Clarke's mean figure. The 

 work of the International Geodetic Association 

 was then taken up and a summary given of its 

 recent investigations in the variations of lati- 

 tude. The fact was noted that it is proposed 

 in the near future to establish four international 

 stations, two of which will be in the United 

 States, and all of which will be within half a 

 mile of the parallel 39° 8'. The most favorable 

 conditions for successful work at these stations 

 were described as well as the mathematical and 

 physical reasons bearing on the choice of loca- 

 tion. 



E. D. Preston, 



Secretary. 



the new YORK section OF THE AMERICAN 

 CHEMICAL SOCIETY. 



By invitation of Dr. C. P. Chandler and the 

 authorities of Columbia University the regular 

 meeting of the Society was held Friday evening, 

 May 6th, at Havemeyer Hall, after a dinner in 

 the University restaurant, at which forty-two 

 members were present. Dr. Chandler made an 

 address of welcome and gave a sketch of the 

 inception and development of the Columbia 

 School of Mines and its successor, the present 

 'Faculty of Applied Science.' The Chairman 

 then made some remarks expressing apprecia- 

 tion of the invitation from the University, and 

 of the interest in the Section manifested by 

 supplying the entire program of papers, the 

 reading of which was proceeded with as fol- 



