224 REPORTS ON INVESTIGATIONS AND PROJECTS. 



after having been heated for a long time to 300° in a stream of dry air. This 

 point, of great importance in its bearing on the atomic weight of silver, was 

 attacked last winter with the help of T. S. Woodward. The positive detec- 

 tion of minute traces of water is always a very difficult matter, and the search 

 in this case was especially perplexing and is not yet concluded ; nevertheless 

 it is safe to say that the results thus far indicate the almost if not quite com- 

 plete absence of water from the fused perchlorate. 



The preparation for publication of such portions of these and previous 

 investigations as have been finished was greatly delayed during the past 

 winter by two circumstances, namely, the writing of the Faraday Lecture and 

 the planning of the new Wolcott Gibbs Memorial Laboratory. This building, 

 to be erected by means of funds generously subscribed by friends of Harvard 

 University, will greatly improve the conditions of experimentation. It is 

 hoped that thereby the funds of the Carnegie Institution of Washington may 

 be used to greater advantage than before. 



GEOLOGY. 



Chamberlin, T. C, University of Chicago, Chicago, Illinois. Grant No. 708. 



Study of fundamental problems of geology. (For previous reports see 

 Year Books Nos. 2-9.) $4,000 



The work of the year under this grant has been an extension of that of last 

 year on the secular maintenance of the atmosphere. The work has deployed 

 into several special lines inseparably connected with the problems of mainte- 

 nance, but which also lie in the broader field of paleo-climatology, and the 

 scope of the paper in preparation has been extended. 



Moulton, F. R., University of Chicago, Chicago, Illinois. Grant No. 709. 



Investigations in cosmogony and celestial mechanics. (For previous 

 reports see Year Books Nos. 4, 5, 8, and 9.) $2,000 



During the last year the following papers have been published : 



(i) The straight line solutions of the problem of N bodies. The Annals of Mathe- 

 matics, vol. 12, No. I, pp. 1-17. Oct. 1910. 



(2) (In collaboration with Dr. W. D. MacMillan.) On the solutions of certain types 



of linear differential equations with periodic coefficients. American Journal 

 of Mathematics, vol. 22, No. i, pp. 63-96. Jan. 191 1. 



(3) The influence of astronomy on mathematics. Science, vol. 33, pp. 357-364. Mar. 



1911. 



During the last year the following book and papers have been completed 

 and accepted for publication : 



(i) Periodic Orbits, a book of 855 manuscript pages, which will be pub- 

 lished by the Carnegie Institution of Washington. 



(2) The Problem of the Spherical Pendulum from the Standpoint of 

 Periodic Solutions. This paper is in type for Rendiconti ]\Iatematico di 

 Palermo. 



