June 19, 1919] 



NATURE 



317 



similar chemical and mechanical constitution, the 

 resemblance having unwittingly been evolved. 



Similarly, the study of the variation with grade 

 in the mineral constitution of a sand presents 

 results of great interest. The detrital minerals oc- 

 curring \\\ each grade vary in proportion, species, and 

 physical characters. Generally speaking, the per- 

 centage weight of the heavy detrital minerals in any 

 r.ide varies inverselv with the grade size. 



P. G. H. B. 



THE AMERICAN PHILOSOPHICAL 

 SOCIETY. 



THE annual general meeting of the American 

 Philosophical Society was held on April 24-26, 

 and a programme of more than fifty papers covering 

 a wide range of subjects was presented. The sessions 

 xvere presided over by the president, Prof. W. B. 

 Scott, and by Vice-Presidents G. E. Hale, H. L. 

 Carson, and A. A. Noyes. 



Two important features were a symposium on the 

 solar eclipse of June 8, 19 18, and one on chemical 

 warfare. In the former, special attention was given 

 to photographs and their interpretation of the promin- 

 ences and the coronal arches and streamers obtained 

 bv members of the several expeditions sent from the 

 Lick, the Mount Wilson, the Lowell, the Sproul, and 

 the Yerkes Observatories. Several conspicuous 

 prominences were shown, and these were generally 

 surrounded by complex coronal structures. These 

 coronal arches or " hoods " are probably among the 

 most notable and remarkable photographed to date. 

 Thev point to an intimate relation between the 

 prominences and the surrounding coronal structure. 

 From the comparison of the observations of earlier 

 eclipses made at different epochs of solar activity, it 

 seems probable that complex coronal detail and dis- 

 turbed regions of the corona around the prominences 

 are more pronounced near sun-spot maxima. 



The symposium on chemical warfare was impressive 

 a> indicating the enormous quantities of poisonous 

 gases, phosgene, mustard, and chloropicrin, made by 

 the United States and shipped to Europe. Col. M. T. 

 Bogert, who was in charge of the General Chemical 

 Warfare .Service, gave a brief historical introduction. 

 He was followed by Col. F. M. Dorsey, who spoke 

 on "Chemical Warfare and Manufacturing Develop- 

 ment"; while Col. W. H. Walker gave an address 

 on the production of chemical warfare munitions. 

 ( "ol. Bradley Dewey treated in detail the American 

 means of defence against the deadly gases used in 

 war, and told how more than five million gas-masks 

 were made in eight months and sent overseas with 

 nearlv three million canisters for holding the absorb- 

 ing chemicals, and how these chemicals were ob- 

 tained, one item being four hundred tons a day of 

 coconut-shells and peach-stones for producing the 

 rharcoal necessary. 



A paper on "Detection of Submarines" bv Dr. 

 IT. C. Hayes, who was stationed at the Naval Experi- 

 mental Station at New London, discussed various 

 l)ossible methods. The most efl'ective one resulted 

 from the development of a svstem of multiple sound- 

 sensitive receivers mounted in such a way as to trans- 

 mit to both ears of the observer a cumulative or 

 summational impulse which becomes a maximum 

 when the instrument is properly directed, thus show- 

 ing the direction of the submarine. It is clear that 

 such an instrument would be valuable in peace-time 

 also in indicating the presence and direction of vessels 

 in a fog. 



Col. Augustus Trowbridge, recently attached to 

 Gen. Pershing's staff, and in charge of the Sound- 



NO. 2590, VOL. 103] 



ranging Service of the A.E.F., analysed the work of 

 this Service, the success of which was remarkable. 

 The location of active enemy batteries and of the 

 direction of fire of friendly guns by means of sound 

 is new, while that by visual means — flash ranging — is 

 an outgrowth and extension of standard artillery 

 methods. 



A sound-ranging section was in the field with the 

 first American Division, March, 1918, while on the 

 date of the armistice the entire front of the 2nd 

 American Army was covered by both flash- and sound- 

 ranging sections. The "central" or calculating 

 station, situated generally in a dug-out or ruined 

 house, was more elaborate than in the case of the 

 flash because of the greater instrumental installation 

 of the sound-ranging section. The "central" instru- 

 ment recorded photographically the time of arrival of 

 the sound of enemy guns at a series of instruments 

 at surveyed positions near the front line and covering 

 a length of about five miles. This instrument de- 

 livered automatically developed and fixed photographic 

 records in less than a minute after the sound of the 

 enemy gun reached the front line, and this record 

 could be interpreted by the use of quick graphical 

 methods, so that the position of the enemy gun could 

 be telephoned to the friendly artillery in about a 

 minute more. The probable accuracy of the location 

 could be given, and also the calibre and target of the 

 piece which had iust fired. The service was not inter- 

 fered with by rain or fog or darkness, though it was 

 rendered less accurate by strong winds. Calculations 

 were rendered difficult" by great artillery activity, 

 though not impossible except under actual "barrage" 

 conditions. 



In ranging the friendly artillerv on enemy objec- 

 tives it was possible to range all the guns of the 

 battery simultaneously, thus effecting considerable 

 time-saving over other methods of ranging. If the 

 ranging was being done on an enemy battery which 

 had just fired, the accuracy attained was very great 

 Cless than twenty-five yards) because of the fact that 

 in this case no wind or temperature corrections need 

 be applied in the calculations. 



A popular lecture, followed by a reception, was given 

 on the Fridav evening by Prof. Arthur G. Webster 

 on "Recent Applications of Physics in Warfare." 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge. — Col. C. S. Myers and Lieut. H. W. 

 Phear have been elected fellows of Gonville and Caius 

 College. 



M.'iN'CHESTER.— Mr. W. L Bragg has been appointed 

 to the Langworthy chair of physics in the University 

 of Manchester in succession to Sir Ernest Rutherford. 



Prof. D. H. Macgregor has been appointed to the 

 Stanlev Jevons chair of economics in succession to 

 Prof. iS. J. Chapman, and Prof. O. T. Jones to the 

 chair of geology in succession to Sir T. H. Holland. 



Oxford. — The statute for the reform of Respon- 

 sions, which lately passed Congregation, came on 

 June 17 before a well-attended meeting of Convoca- 

 tion. After speeches in favour of the statute by Mr. 

 E. Barker, fellow of New College, and Mr. C. Nor- 

 wood, Headmaster of Marlborough, and against it 

 by Mr. E. Walker, fellow of Queen's, and the Regius 

 professor of Greek (Prof. Gilbert Murray), a division 

 was taken, from which there appeared 306 for the 

 statute and 312 against it. The chief resident oppo- 

 nents of the statute have, however, pledged themselves 

 not to resist a proposal by Prof. Gilbert Murray to 

 introduce a statute on the earliest opportunity which 

 will provide for the exemption from compulsory Greek 



