10 



SCIENCE 



[N. S. Vol. LI. No. 1305 



and tlie rates of clocks depend in the first 

 place on their gravitational fields, which again 

 are produced by the material systems con- 

 cerned. 



Thus the new theory of gravitation diverges 

 widely from that of Newton with respect to 

 its basal principle. But in practical applica- 

 tion the two agree so closely that it has been 

 difficult to find cases in which the actual 

 differences could be subjected to observation. 

 As yet only the following have been sug- 

 gested : 



1. The distortion of the oval orbits of 

 planets round the sun (confirmed in the case 

 of the planet Mercury). 



2. The deviation of light-rays in a gravita- 

 tional field (confirmed by the English Solar 

 Eclipse expedition). 



3. The shifting of spectral lines towards 

 the red end of the spectrum in the case of 

 light coming to us from stars of appreciable 

 mass (not yet confirmed). 



The great attraction of the theory is its 

 logical consistency. If any deduction from 

 it should prove untenable, it must be given up. 

 A modification of it seems impossible with- 

 out destruction of the whole. 



No one must think that Newton's great 

 creation can be overthrown in any real sense 

 by this or by any other theory. His clear and 

 wide ideas will for ever retain their signifi- 

 cance as the foundation on which our modern 

 conceptions of physics have been built. 



Albert Einstein 



SCIENTIFIC EVENTS 



THE ANNUAL REPORT OF THE DIRECTOR OF 

 THE BUREAU OF STANDARDS 



A REVIEW of the work of the National Bu- 

 reau of Standards for the year ending Jime 

 30, 1919, is given in the alumni report of the 

 director of the Bureau of Standards at Wash- 

 ington. The report describes the functions of 

 the bureau in connection with standards and 

 standardization, and contains a chart and 

 description of the several classes of standards 

 dealt with. The director also gives a clear 

 idea of the relation of the bureau's work to 

 the general public, to the industries, and to the 

 government, and includes a special statement 



of the military work of the year. Brief state- 

 ments are made upon practically all of the 

 special researches and lines of testing com- 

 pleted or under way at the bureau. The list 

 of these topics occupies 12 pages in the table 

 of contents. 



The bureau is organized in 64 scientific and 

 technical sections and 20 clerical, construction 

 and operative sections. During the year the 

 bureau has issued 51 publications, not inclu- 

 ding reprintings, 36 of which were new and 15 

 revisions of previous publications. In the 

 several laboratories of the Bureau more than 

 131,000 tests were made during the year. 

 The appropriations for the year, including 

 special funds for war investigations, were ap- 

 proximately $3,000,000. A noteworthy event 

 of the year included the completion of the 

 industrial laboratory in which will be housed 

 the divisions having to do with researches and 

 tests of structural materials. The building 

 also includes a commodious kiln house for 

 use, among other purposes, of the ceramics 

 division in the experimental production of new 

 clay products and for general experimental 

 purposes. 



The report comprises 293 pages and may be 

 obtained as long as free copies are available 

 by addressing the Bureau of Standards, Wash- 

 ington, D. C. 



NEEDS OF THE COAST AND GEODETIC SURVEY 



Declaring that the work of the United 

 States Coast and Geodetic Survey, which pro- 

 vides the navigating charts which are the 

 direct means of protecting from loss the 

 vessels of our navy. Coast Guard, and mer- 

 chant marine, is seriously hampered by lack 

 of funds, the superintendent of the survey 

 makes an appeal for an adequate appropria- 

 tion to remedy this situation, in his annual 

 report to the secretary of commerce. 



In order to make and put these naviga- 

 tional charts into the hands of all who de- 

 mand them both the field and office forces 

 must be kept up to the highest standards of 

 efficiency, and this can not be done without 

 sufficient funds to maintain and operate 

 modem surveying vessels and obtain able 

 officers and crews to man them. In addition 



