6l2 



NATURE 



[February 5, 1920 



OVR ASTRONOMICAL COLUMN. 



Comets. — The object announced last week as 

 comet 19200 appears to be a minor planet. It was 

 so described by the discoverer, but through some 

 telegraphic confusion was reported as a comet. 



Two comets were discovered in December. The 

 first, 1919/, was recorded on two plates taken on 

 December lo at Bergedorf, Hamburg, bv Dr. Baade. 

 It is probably identical with Holmes's comet, for 

 which a search ephemeris had been calculated. If so, 

 perihelion passage occurred about November 22. 



Comet 1919,4? was discovered by Mr. J. F. Skjellerup 

 at the Cape of Good Hope on December 18, and was 

 also observed by Mr. Woodgate at the Cape Observa- 

 tory. Dr. Halm sends the following provisional 

 elements : 



T= 1920 January 2674 G.M.T. 

 w =276° 35' 



Q=3i5^ 36' 



1 =123° 10' 



log ^ = 9-47376 



The elements bear some resemblance to those of the 

 comet of 1797, also to 1808 I. 



Ephemeris for Greemvich Midnight. 



R.A. S. Decl. Log r Loj A 



h. m. s. D / 



Feb. 10 ... 20 31 52 4 34 00189 02869 



N. Decl. 



20 ... 20 34 28 o 7 0-0934 0'3095 

 March i ... 20 36 8 4 29 0-1541 03245 

 II... 203642 843 0-2049 0-3337 

 The comet is now rather close to the sun, but should 

 be visible in the morning in March. 



The Motion of the Moo.n. — Dr. j. K. Fothering- 

 ham contributed a paper on this subject to the Royal 

 Astronomical Society in January. He showed, as 

 others have done, the necessity for applying an em- 

 pirical term to the moon's longitude, and the im- 

 possibility of determining both that term and the value 

 of the secular acceleration from modern observations 

 alone. Accordingly, various periods were assumed for 

 the empirical term, and the corresponding values of 

 the acceleration deduced. The period 254 years is 

 preferred, as this gives the same value 10" for the 

 acceleration as that deduced from ancient eclipses. 

 Prof. Turner had found a period of about 240 years 

 from a discussion of Chinese earthquakes and Nile 

 floods. It was suggested that the two periods might 

 be identical, and that the apparent oscillation in the 

 moon's motion was really a change in the earth's 

 period of rotation. 



The observations used extend to the end of 1918, 

 ten years later than those used by Drs. Brown and 

 Cowell. These additional ob.servations have consider- 

 able influence on the result. 



Stars of High Velocity.— In most studies of 

 stellar motions the stars with abnormally high velo- 

 cities are excluded, which is doubtless a sound principle. 

 Nevertheless, an examination of these motions is of 

 great interest, and was undertaken by Messrs. W. S. 

 Adams and A. H. Joy (Proc. Nat. Acad. Sci., Washing- 

 ton, July, 1919). The highest velocitv in space found for 

 any star is 494 km. /sec. for the 9th mag. star A.G. 

 Berlin 1366. On the average, the two components 

 of the velocity in the galactic plane are about equal, 

 and 24 times the component perpendicular to the 

 plane. Nearly a hemisphere in galactic longitude is 

 devoid of apices, the values all lying between 131° 

 and 322°. The centroid of the' thirty-seven stars 

 examined has a velocity exceeding 74 km. /sec, almost 

 exactly in the galactic plane. These facts seem to 

 establish that the velocities have been generated 

 NO. 2623, VOL. 104] 



within our own star system, and that the stars are 

 not mere visitors from outside, as has sometimes been 

 suggested. They are probably mostly of small mass, 

 but this can scarcely be the case with .\rcturus, the 

 high velocity of which remains an enigma. It is 

 noted that twenty-six out of the thirty-seven stars 

 are of spectral types F and G. 



THE ST. LOUIS MEETING OF THE 

 AMERICAN .ASSOCIATION. 



^pHE seventy-second meeting of the American 

 -•- Association for the .Advancement of Science was 

 held in St. Louis, Mo., on December 29 to January 3, 

 under the presidency of Dr. Simon Flexner, director 

 of the Rockefeller Institute for Medical Research, 

 New York City. The meeting was a most successful 

 one, the attendance of scientific men reaching approxi- 

 mately twelve hundred. St. Louis is the fourth city of 

 the United States in size, and is an extremely pro- 

 gressive centre, paying much attention to educational 

 matters and possessing two universities, two admir- 

 able medical schools, an academy of science, the great 

 Missouri Botanical Gardens, and an extraordinarilv 

 advanced system of institutions for secondary educa- 

 tion. All the meetings (and there were thirty-two dis- 

 tinct organisations meeting at the same time, twelvi; 

 of them being sections of the association) were held 

 in the single building known as the Soldan High 

 School. In this building there are very many large 

 lecture-rooms with lantern and laboratory facilities, 

 one auditorium with a seating capacity of more than 

 two thousand, and a dining-room with about the 

 same accommodation, and thus the necessity of meet- 

 ing in distinct and sometimes widely separated build- 

 ings, as has occurred ia other cities, was avoided. 



The opening session was held on Monday night, 

 December 29. Chancellor Hall, of Washington Uni- 

 versity, St. Louis, delivered an address of welcome, 

 and the retiring president. Prof. John Merle Coulter, 

 gave his address (published in Nature of January 29. 

 p. 581) on "The Evolution of Botanical Research." 



On the following night a lecture, complimentary to 

 the citizens of St. Louis, was delivered by Presiden: 

 Simon Flexner on the general subject of the medical 

 outlook in research. The trend of the address was 

 optimistic, and the subjects especiallv mentioned were 

 influenza, yellow fever, poliomvelitis, and cancer. 



During the week addresses by chairmen of sections 

 were delivered as follows: — Section .\, "Recent Pro- 

 gress in Dynamics," George D. Birkhoff ; Section B, 

 "Some .lAspects of Physics in War and Peace," 

 Gordon F. Hull; Section D, "Science and Modern 

 Engineering," Ira N. Hollis ; Section E, "Geology as 

 Taught in the LInited States," David White ; Sec- 

 tion H, "The Relations of .'\nthropologv and Psycho- 

 logy," .Ales HrdliCka; Section I, "New .After-the-War 

 Phases of Practical Pan-.Americanism," John Barrett; 

 .Section K, "The Untilled Fields of Public Health," 

 C. E. A. Wlnslow; Section L, "The Part Played bv 

 Heredity and Maturity as Factors Conditioning the 

 Effects of Training," Stuart A. Courtis ; and Sec- 

 tion M, "The Organisation of Research," Henry P. 

 .Armsby. 



There were also a number of symposia, which 

 attracted much attention, as follows: — "World 

 Standardisation " and "Education and Practical Work 

 on the Metric Basis," under the auspices of the 

 .American Metric .Association; "The Life-cycle in 

 Insects," under the auspices of the Entomological 

 Society of America; "The Relation of the Use of 

 Power and Labour-saving Machinery to Agricultural 

 Progress," under the auspices of Section M; "The 

 .Adjustment of .Agricultural Teaching and Research 



