674 



NATURE 



[February 19, 1920 



below the normal in all months except December. 

 The defect was marked in July, August, and Septem- 

 ber. During 1918 a daily journal of the weather over 

 the Indian Ocean was kept by means of observations 

 obtained from ships' log-books. The logs of sixty 

 voyages were copied. So far as is known, there were 

 five cyclones in the South Indian Ocean during the 

 year 1918. The daily records of observations pub- 

 lished each month are of considerable value in adding 

 to our knowledge of the physics of the globe. Epochs 

 of diurnal range are regularly shown by the several 

 instruments. The velocity of the wind at the Mauritius 

 Observatory is seen to increase very regularly at the 

 midday hours and to fall off during the night, the 

 range frequently being shown even on days when the 

 normal trade winds are interrupted. The seismograms 

 record sixty-seven earthquakes during 1918. 



The January number of the "Abstracts of Papers" 

 issued by the Institution of Civil Engineers contains 

 235 pages, twelve of which are devoted to name and 

 subject indexes. The abstracts, of which there are 

 387, are classified under the six heads : Measurement, 

 Materials, Structures, Distribution of Energy, Ap- 

 pliances, and Specialised Practice. Each head is, as 

 a rule, subdivided into sections. It is impossible to 

 read through the abstracts without realising the im- 

 portance to the future of the engineering profession 

 in this country of a knowledge of the progress which 

 is taking place in the practice of engineering through- 

 out the world. From the number of abstracts devoted 

 to it, the question of fuel economy appears to have 

 been taken up with vigour in America and in Ger- 

 many. In the former country the use and advantages 

 of pulverised low-grade coal have been investigated, 

 and it appears that 75 to 80 f>er cent, efficiencies can 

 be obtained with it in boilers of all sizes. In Ger- 

 many the utilisation of the waste heat from iron and 

 steel furnaces to generate steam in boilers is being 

 strongly advocated as the best form of economy. 



The reviewer of part i. of "The Daily Telegraph 

 Victory Atlas of the World," in Natijre of Novem- 

 ber 13, 1919, remarked, towards the end of. a favour- 

 able notice : " The changes due to the Peace Treaty 

 are incorporated, but a mistake is made in the area 

 of the Slesvig plebiscite." The publishers of the 

 map, Messrs. Geographia, Ltd., wrote at the time 

 to say that the boundary shown on their map was 

 correct. The reviewer's comment, as stated in our 

 issue of December 25, p. 419, was based upon the 

 abstract of the Treaty of Versailles, and the recent 

 publication of the Treaty has enabled him to com- 

 pare its wording with the large-scale map of Slesvig. 

 He now writes to acknowledge the correctness of 

 Messrs. Geographia 's map in this respect, and to 

 apologise for his mistake. We on our part much 

 regret that, on a point of fact, a review in our 

 columns should have contained a statement which 

 now proves to be in error, and that, in consequence, 

 the accuracy of a particular frontier line on Me.ssrs. 

 Geographia's production was wrongly questioned. 



Messrs. W. Heifek and Sons, Ltd., Cambridge, 

 have in the press " The Theory of Direct-current 

 Dynamos and Motors : .\ Text-book for University 

 NO. 2625, VOL. 104] 



Students of Electrical Engineering," by J. Case, which 

 has been written to fill the gap between books of 

 general electrical engineering and the specialised ones 

 dealing with designs. The aim has been to furnish the 

 student with a fairly comprehensive study of the prin- 

 ciples and theories underlying the design of direct- 

 current dynamos and motors, and the work will con- 

 tain many worked examples ; also exercises for the 

 student. The notation adopted is that of the Inter- 

 national Electrotechnical Commission. 



Mr. C. Baker's classified list (No. 68) of second- 

 hand scientific instruments includes in one of its 

 sections a number of microscopes and accessories 

 which should be of particular interest at the present 

 time to students and other workers. There are also 

 sections on surveying and astronomical instruments, 

 spectroscopes and projection apparatus, and other 

 instruments. 



Mr. L. T. Hogben wishes to direct attention to an 

 omission in the abstract of his Royal Society paper, 

 "Studies in Synapsis," i., reprinted in Nature of 

 February 12 (p. 649). He does not conclude that 

 abortive spindles characterise the Hymenoptera in 

 general, but only the Hymenoptera parasitica. 



OUR ASTRONOMICAL COLUMN. 



Mercury as an Evening Star.— This planet will 

 reach its greatest easterly elongation (18° 11') on 

 March 3, and set at about that date rather more than 

 an hour and three-quarters after the sun. This 

 will be the most favourable period of the year for 

 viewing Mercury in the evenings. The intending 

 observer should look tow'ards the east-by-south region 

 of the horizon, and when the atmosphere is clear th< 

 planet will be seen about an hour after sunset at; a 

 low altitude. It will set on February 26 at 7.5 p.m., 

 on March 4 at 7.31 p.m., and on March 11 at 

 7.23 p.m. 



Centenary of the Royal .Astronomical Society. — 

 .\t the annual general meeting of this society held 

 on February 13, the president, Prof. A. Fowler, 

 gave an address on the foundation of the societj' 

 just a century before. The four men who 



were most influential in its formation were the 

 Rev. William Pearson, Mr. Francis Baily, ,Sir 

 John F. W. Herschel, and Mr. Charles Babbage. The 

 two latter both lived until 187 1, and there are no 

 fewer than fifteen surviving fellows whose fellowships 

 overlapped with theirs. One of these, Mr. Inwards, 

 said that he remembered speaking to Sir John 

 Herschel at a meeting of the Society. There was at 

 first a good deal of opposition to the new society on 

 the part of the Royal Society, and the Duke of 

 .Somerset, who was elected the first president, quickly 

 resigned this office owing to the pressure brought to 

 bear upon him. He was succeeded after an interval by 

 Sir William Herschel, who was then eighty-two years 

 of age, and died in 1822. Mr. Stephen Groombridgej 

 well known for his Star Catalogue, was another 

 the original members. They were not called fellov 

 until 1830, when the Royal Charter was granted 

 givinsj the society its present title; it was previous^ 

 , called the London .Xstronomical Society. The earlie| 

 publications of the Society were in the form 

 memoirs; the Monthly Notices did not commenc 

 until several years later, and were at first only small' 

 pamphlets containing ephemerldes of comets and other 

 matters of transient interest. 



