December 5, 19 12] 



NATURE 



393 



store, i;; bakery, o'8 ; barber, 12; cigar, 14 ; cloth- 

 ing- i'5 ; confectionery, I'o; delicatessen, i"i; drug, 

 i'2 ; dry g-Qods, I'o; florist i"i; grocery, I'o; haber- 

 dashery, i'7; jewellery, 1'6; meat, o'g ; millinery, i'3 ; 

 music, I'l; restaurant, I'l ; shoe, i'o; stationery, i'o; 

 wine I'o watt per square foot of floor. 



The October issue of Science Progress contains a 

 full account, by Mr. W. A. Davis, of the experiments 

 on the chemical effects of light, to which so much 

 attention has been directed in recent years. The changes 

 produced may be of some half-dozen tj'pes. The most 

 important of these is probably a reciprocal o.\idation 

 and reduction, but isomeric and polymeric change, 

 synthesis and hydrolysis are also effected in many 

 cases. These changes are somewhat irregular in their 

 occurrence ; thus the nitrobenzaldoximes undergo 

 isomeric change on exposure to light, whilst the 

 parent substance remains stable; again, maleic acid 

 is converted into fumaric acid by light in presence of 

 bromine, but the other halogens do not produce this 

 eftect. One of the most striking changes is that of 

 «i7o-cinnaniylidene acetic acid, 



C„H,.CH : CH.CH : CH.CO.H, 

 which, when dissolved in benzene with 3 per cent, 

 of its weight of iodine, actually sets within three 

 minutes on exposure to light, owing to the conversion 

 of 80 per cent, of the acid into a less soluble isomeride ; 

 in the dark no change occurs in six davs. 



\A"e have received from the Carnegie Institution of 

 Washington a monograph on the conductivity, &c., 

 of aqueous solutions of salts and org.inic acids, by 

 Prof. H. C. Jones. As this summarises the data that 

 have been pulished in a series of American papers, it 

 will be of considerable value to those who have to 

 refer to the figures now collected. In the original 

 papers the data for the range 0° to 35° C. were all 

 issued separately from those from 35° to 65° C. ; in 

 such cases the advantages of publishing in bulk rather 

 than in successive portions cannot be emphasised too 

 strongly. The present publication is therefore doubly 

 welcome. 



Messrs. T. C. and E. C. Jack have added another 

 dozen volumes to their " People's Books," which are 

 published in cloth binding at 6d. net. The additions 

 include a volume by Dr. T. G. Bonney, F.R.S., en- 

 titled "The Structure of the Earth," in which he gives 

 a very brief statement of the problems and methods 

 of geology, and a popular account of the disintegrat- 

 ing forces at work modifying the earth's crust, of 

 volcanoes, land movements, and the life-history of the 

 earth. In " Hypnotism and Self-Education," Dr. 

 A. M. Hutchison writes on the present-day position 

 of medicine as regards diseases which demand healing 

 other than that which can be given by drugs. A 

 volume by Mr. William Hall, R.N., on "Navigation," 

 is intended to initiate the reader "as a sort of honorary 

 member in the great company of seafarers," and ex- 

 pounds simply such subjects as dead reckoning and 

 astronomical navigation. Mr. R. G. K. Lempfert, 

 superintendent of the Forecast Division of the 

 Meteorological Office, describes in his volume 

 "Weather Science" how meteorological observations 

 NO. 2249, VOL. 90] 



are made and their relation to the changes going on 

 in the atmosphere, and explains what can be learnt 

 by combining the results of observations taken at a 

 number of stations. Two other of the books — "Mar- 

 riage and Motherhood," by Mr. H. S. Davidson, and 

 "The Baby : A Mother's Book," by a Mother, provide 

 in simple words the information with which every 

 wife and mother should be familiar. 



In view of the increasing importance of the studv 

 of public hygiene, the syndics of the Cambridge Uni- 

 versity Press have decided to publish a series of 

 volumes dealing with the various subjects connected 

 with public health. The provisional lists of subjects, 

 all of which will be treated by experts, include :• — 

 The causation of tuberculosis, house-flies and disease, 

 bacteriology of foods, tropical hygiene, sewage dis- 

 posal, water purification, school hygiene, sound and 

 unsound foods, domestic sanitation, chemical analyses 

 of foods, &c. It is intended that the whole series shall 

 appeal not only to medical men but also to those 

 engaged in the study or administration of public 

 health at home or abroad. The series will be under 

 the p^eneral editorship of Dr. G. S. Graham-Smith 

 and Mr. J. E. Purvis. 



Messrs. Kegan Paul, Trench, Trubner and Co., 

 Ltd., are about to publish a work on the "Theory of 

 Evolution," by the Rev. K. Frank, S.J., with a 

 chapter on ant guests and termite guests, from the 

 pen of Father E. Wasmann, S.J. The work has been 

 translated from the German by Mr. C. T. Druerv, and 

 will be illustrated. 



OUR ASTRONOMICAL COLUMN. 



Radium in the Chromosphere. — In No. 454 of The 

 Observatory, Dr. Dyson replies to the views expressed 

 by Mr. Evershed and Mr. Mitchell concerning his 

 suggestion that there is some evidence for the exist- 

 ence of radium among the elements spectroscopically 

 disclosed in the solar chromosphere. 



His contention is that the chromospheric spectrum 

 is an enhanced-line spectrum, and that before accept- 

 ing any coincidence of Fraunhoferic and chromospheric 

 lines as evidence of identity of source, the behaviour 

 of any line in question in the spark should be taken 

 into account. On these grounds he questions Mr. 

 Mitchell's identifications of the lines A4699'52 and 

 '^4533'34_ with lines given by Rowland. Other cases 

 are against the radium identifications, however, and 

 Dr. Dyson expresses the hope that the question will 

 receive attention at future eclipses, and that the 

 radium line at A58i3'g, referred to by Mr. Evershed, 

 will be looked for. 



Observations of Jupiter. — Despite the unfavour- 

 able conditions of altitude and weather some interest- 

 ing observations of Jupiter were made during May- 

 July at the observatory of the French .iXstronomical 

 Society, and the results, with drawings, are now pub- 

 lished in the November number of L'Astronomie. 



The north polar region was much darker than the 

 neighbouring region during May, but later it cleared 

 until its hue was similar to the north temperate 

 zone. Great changes of form and relative movement 

 were observed in the great southern perturbation, and 

 about the middle of July the displacement W'as at the 

 rate of about 1000 kms. per day ; these changes are 

 illustrated by curves and drawings. Later observa- 



