October 21, 1909J 



NA TURE 



ties is badly needed is street lighting. It is pointed 

 out that there is room for the establishment of some 

 central testing department where thoroughly trustworthy 

 and impartial tests could be carried out and used for the 

 common benefit of those interested. In particular, it is 

 suggested that it cannot be decided by the mere personal 

 impression of a non-technical body of observers whether 

 the lighting of the street is good or bad. This must be 

 determinedly the aid of precise scientific tests, carried out 

 by impartial experts, who have made a thorough study 

 of the subject, and can provide records by which experi- 

 ences can be checlced and subsequently repeated. 



Other instances of problems in illumination in which 

 there is great field for scientific treatment are shop-window 

 lighting, stage lighting, and light-house illumination ; in 

 the two former fields, in particular, there is ample scope 

 for the ingenuity of those who are up-to-date in their 

 knowledge of the different illuminants, and possess, in 

 addition, the requisite taste. 



In the next section of this lecture Mr. Gaster deals with 

 the scientific basis of light production, pointing out how 

 the nature of the radiation from an illuminant depends 

 in general upon its temperature, and indicating some of 

 the possible lines of future development. The figures of 

 authorities in this matter differ very greatly, but it is 

 generally considered that the percentage of energy radiated 

 in the form of light is very small indeed. The problem 

 of light production is complicated by the fact that some 

 invisible kinds of radiation seem to exert a prejudicial 

 effect on the eve. The author describes some exoeriments 

 showing the nature of the ultra-violet rays, which some 

 authorities consider to be injurious. 



In conclusion, Mr. Gaster points out th.at the problem 

 of illumination is a comolex subject which deserves speci.nl 

 consideration by itself. There is a need for men who are 

 not connected with any particular illuminant and who are 

 able to take a wide view of the different aspects of the 

 matter, so as to deal with modern problems of lighting. 

 In order to focus interest in this subject and to bring into 

 contact the engineers, architects, oculists, and others 

 interested in illumination, a society has been formed this 

 year which will, it is hoped, graduallv lead to the solution 

 of the important questions on which further exact d.nta are 

 felt to be desirable; this is termed the Illuminating 

 Engineering Society. The first president of the .societv is 

 Prof. S. P. Thompson, and the opening session will com- 

 mence in November. 



ANNVAL METEOROLOGICAL REPORTS. 

 T^HE Deutsche Seevvarte has issued part xvii. of its over- 

 ■*■ sea meteorological observations for 1907, containing 

 very carefully prepared summaries, and in some cases in- 

 dividual readings, at some thirty stations. The principal 

 localities include Labrador, Morocco, Shantung, German 

 East Africa, and some islands in the Pacific Ocean ; there 

 are also some isolated stations, including one recently 

 established at Babylon. Scientific investigators will be 

 grateful to the Seewarte for references which are given 

 in all cases to the periodicals in which previous observa- 

 tions and results have been published. 



The annual report of the Philippine Weather Bureau for 

 iqoy, part i., contains hourly readings at the Manila 

 Observatory, together with means deduced therefrom. The 

 tables also show the extreme values recorded, and the 

 departures of the monthly and yearly means from the 

 average. The mean temperature of the year, 79-5°, was 

 practically normal; the absolute extremes were 98-1° in 

 April and 59-0° in January. The rainfall, 72-5 inches, 

 was 33 inches below the average ; of this amount 64 inches 

 fell from June to October inclusive (the period of the south- 

 west monsoon). .An appendi.K shows the greatest daily 

 and hourly rainfall registered at the observatory in past 

 years; the greatest daily falls were 133 inches and i2-i 

 inches, on September 24 and 25, 1S67. 



The report of the Liverpool Observatorv for the vear 

 IQ08 has been received from Mr. W. E. Plunimer. This 

 useful establishment is maintained by the Mersey Docks 

 and Harbour Board in the interest of shipping, and is 

 well provided with meteorological and astronomical instru- 



NO. 2086, VOL. 81] 



ments. In addition to the continuous use of the transit 

 instrument for the determination of time, observations of 

 selected stars and of comets visible from the observatory 

 formed the chief astronomical work of the year. A Milne 

 seismograph for the registration of tremors in the earth 

 is kept steadily at work ; during the Messina earthquake 

 (December 2S) the duration of disturbance was ih. 41m., 

 and the amplitude (half the complete range of maximum 

 motion) was 15 mm. The meteorological results are very 

 complete, e.g. the wind observations show the maximum 

 velocity for each day recorded by Dines's apparatus, the 

 extreme pressure on the square foot by Osier's anemo- 

 meter, the horizontal motion by Robinson's anemometer, 

 and the number of hours that the wind blew from different 

 points of the compass. The mean temperature of the year 

 (492°) was practically normal, and the rainfall (28-9 inches) 

 slightly above the average. 



The annual report of the United States Weather Bureau 

 for the fiscal year ended June 30, iqoS, shows that the 

 research work at Mount Weather Observatory has been 

 carried on without material curtailment, notwithstanding 

 the destruction by fire of the administration building in 

 October, 1907. Investigation of the upper air by means 

 of kites and captive balloons is made daily (except Sundays), 

 and the data are telegraphed to Washington for the use of 

 the forecast division. The work on solar physics includes 

 the measurement of solar radiation and the degree of 

 absorption by the atmosphere. Considerable discrepancies 

 exist in the values of the solar constant, even computed 

 from observations on the same day at Mount Weather 

 and at Washington ; in most cases these are traceable to 

 the unsteadiness of the atmosphere. Great activity exists 

 in the divisions dealing with land and ocean meteorology; 

 the number of climatological stations now exceeds 3700, 

 and more than 1600 vessels cooperated with the Bureau 

 during the year. .Ml data referring to the Indian Ocean 

 are lent to the Indian Meteorological Department, wheie 

 they are copied and returned. In the forecast division 

 isobaric charts are prepared from daily telegraphic reports 

 from selected stations throughout the northern hemisphere, 

 and forecasts for about a week in advance were published 

 during the last three months of the year. The library 

 now consists of about 28,000 books and pamphlets.^ In 

 addition, meteorological articles contained in periodicals 

 and trans.actions are catalogued under both author, and 

 subject ; this bibliography is said to be more frequently 

 consulted than the catalogue of books. 



The Survev Department of Egypt has pubhshed its 

 meteorological report for 1907, containing hourly readings 

 at Helwan and climatological tables at thirty-five stations 

 of the second and third order ; the monthly tables give tri- 

 daily readings in the form ■ adopted by the International 

 Meteorological Committee, and also include the daily 

 amount of evaporation, as that element is of considerable 

 importance in Egypt and the Sudan. .Additional tables 

 include hourly observations by Dines's pressure anemometer 

 at .Mexandria, rainfall and wind direction for a number of 

 stations, and river-gauge observations. In compliance 

 with a desire expressed by the International Meteoro- 

 logical Committee in 1907, tables of normal values are 

 also given. Rainfall was in excess in Egypt and in 

 North Sudan, but in considerable defect throughout the 

 rest of the Sudan, and, as we have previously stated, the 

 Nile flood was worse than any recorded during the past 

 fiftv years. 



The meteorological year-book of the Bremen Observatory 

 for 1908 has been received. From small beginnings this 

 institution, under the superintendence of the late Dr. P. 

 Bergholz, has attained a position of considerable import- 

 ance ; the observations, which include hourly readings 

 and means, with monthly and yearly summaries, have been 

 reduced by Prof. Grosse' in the same thorough manner as 

 heretofore, with the addition of hourly tabulations of sun- 

 shine records and monthly means of earth temperatures. 

 The valuable materials, which now extend over many 

 years, await a general scientific discussion ; this de- 

 sideratum is urgently pointed out by Dr. Grosse, but under 

 present arrangements, while the director has to divide his 

 energies between the observatory and other official duties, 

 this important work has to be postponed. 



