May 6, 1909 J 



NA TURE 



295 



^iresents — as one expects from Dr. van Bemmelen — many 

 ingenious ideas, wliich, if not all equally valuable, are at 

 least suggestive. Observers in tropical countries, for 

 instance, will be interested to learn how he dealt with 

 mosquito troubles, and how he rendered the beats of his 

 chronometer*"audible during rain-storms. To those now 

 engaged in the magnetic survey of India, the work must 

 be one of especial interest. 



The third volume describes the work done in 1906-7 by 

 the Survey of India. Besides interesting details as to 

 pendulum and tidal work, levelling and ordinary survey- 

 ing, it gives an unusually full account of the progress of 

 the magnetic survey under Captain Thomas, R.E. As in 

 previous volumes, there is an account of elaborate instru- 

 mental investigations, but the most novel part is a dis- 

 cussion of formula2 got out by Mr. J. Eccles — acting, appar- 

 ently, on a suggestion by Sir A. Riicker — for deducing 

 the diurnal inequalities of declination and horizontal force 

 at any intermediate place from those recorded at two 

 magnetic observatories. There are comparisons of the in- 

 equalities observed at one magnetic observatory with those 

 calculated for its latitude and longitude from the inequali- 

 ties at two other observatories. The agreement is pro- 

 nounced very satisfactory. The formulae seem based on 

 the assumptions that the diurnal inequality at a given 

 latitude is a function only of the local time, and that for 

 the area concerned the rate of variation with latitude of 

 the departure at any local hour from the mean value for 

 the day is constant both for the northerly and easterly 

 4;omponents of force. 



So limited a hypothesis seems hardly likely to prove 

 very satisfactory unless confined to somewhat restricted 

 areas, and when one looks into the observed and calcu- 

 lated values, especially those for the declination, one finds 

 that, relatively to the amplitude of the inequality, the 

 agreement is less satisfactory than one would have inferred 

 from the comments made. The declination diurnal in- 

 equality, however, in India is so small that even large 

 percentage departures from accuracy would be of minor 

 consequence from a survey point of view. 



Various prospective difficulties are referred to in connec- 

 tion with the distribution of magnetic storms, the difference 

 between mean values from all and quiet days, and similar 

 matters. The nature of the answer to several of the 

 problems mentioned might perhaps be anticipated from what 

 is already known from other sources ; but one cannot avoid 

 a suspicion that, unless India is singularly free from local 

 magnetic disturbances, some of the difficulties referred to 

 may prove to be of secondary importance. It will certainly 

 require no small amount of knowledge and ingenuity to 

 utilise to the full all the refinements which it is intended to 

 introduce into the observational material. 



C. Chree. 



BIRD NOTES. 



T7ROM Dr. Thienemann, director of the Vogelwarte 

 "^ (ornithological station) at Rossitten, on the Baltic, 

 we have received three papers relating to the recent work 

 of that establishment. The first of these, which deals 

 with marked storks and swallows, is an extract from 

 Reichenow's Ornithol. Monatsberichte for October, 1908; 

 the second, in which the migration of storks is discussed 

 at some length, was originally published in Land- und 

 F orstwirkschaftliche Zeitimg for September ; while the 

 third, relating to marked storks in Africa, gives no clue 

 as to its place of publication. A note on this third paper 

 appeared in the Times of .'\pril 5. In connection with 

 these, it may be mentioned that a very interesting article 

 by Mr. A. L. Thomson on the work of the Rossitten 

 station, and more especially the method of marking birds, 

 is published in the .\pril number of Witherby's British 

 Birds. 



As regards the capture of marked storks in Africa, 

 reference in Nature has been already made to the speci- 

 men recently killed in Natal. Dr. Thienemann now tells 

 us of the capture, at Moriia, Basutoland, of a Rossitten 

 bird in February last. This is the most southerly point 

 reached by a stork liberated in east Prussia, but the Natal 

 'bird, which was set free in Hungary, went further, 



NO. 2062, VOL. 80] 



although the distance from the point of liberation was less. 

 Other records include a stork, one of a brood of three 

 inarked near Kbnigsberg in June, 1906, the ring and foot 

 of which were brought by natives to a French officer near 

 Lake Tchad, the bird having been snared in October of 

 the same year on the Fittri Lagoon. A stork from a brood 

 of three, liberated near Koslin, Pomerania, in July, 1907, 

 was taken the following winter near Fort Jameson, 

 Rhodesia. It is now, therefore, certain that European 

 storks habitually inigrate to South Africa, and the next 

 point to ascertain is whether they ever breed south of the 

 equator. 



According to the Times of April 26, the capture of a 

 marked stork near Jerusalem has been reported to the 

 Hungarian Central Bureau for Ornithology, Budapest. A 

 flock of more than 2000 storks alighted to rest by one 

 of the lakes near Jerusalem, and five were caught. The 

 marked bird was hatched at Egri, in eastern Hungary, 

 last season, and marked with the stork-ring No. 293 on 

 July 8, 1908 ; it will be placed in the new Palestine 

 .Museum. The storks seen were on their homeward 

 journey, probably from South Africa. This capture is 

 considered important as showing that these birds do not 

 pass over the Mediterranean Sea, but follow the longer 

 route over the land. 



That the South African honey-guides (Indicatoridae) are 

 parasitic in the matter of egg-laying has been long known, 

 but it appears from a paper by the Rev. Noel Roberts in 

 the April number of the Journal of the South African 

 Ornithologists' Union that this habit is shared by certain 

 moinbers of the whydah-bird group (Ploceids). From a 

 paper in vol. iii.. No. i, of the same journal, it seems 

 that this parasitic habit has been demonstrated in the case 

 of the pied whydah-bird (T'idiia principalis), and in the 

 issue now before us Mr. Noel gives reasons — although 

 these are not quite so clear or convincing as they might 

 be — that the same holds good in the case of the typical 

 species of the genus Quelea. In the author's opinion, this 

 bird deposits its eggs, at all events in soine instances, in 

 the nests of another member of the same family, namely, 

 Pyromelana oryx. It may be hoped that further investi- 

 gations will be undertaken for the purpose of confirming 

 these interesting observations. 



Naturen for April contains a paper, by O. J. Pettersen, 

 on the habits and distribution of the redbreast. 



In the course of his annual report on Norfolk ornith- 

 ology, published in the April number of the Zoologist, 

 Mr. J. H. Gurney comments on the scarcity of nightin- 

 gales, spotted flycatchers, willow-wrens, and various kinds 

 of warblers during the summer of iqo8. This scarcity 

 the author attributes to the great snowfall which took 

 place on .April 23 of that year. Three features in the 

 autumn migration were noteworthy, namely, the number 

 of redstarts on September 23, the great flights of rooks, 

 crows, and starlings on October 18 and 19, and the 

 abundance of woodcock. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge. — .\n anonymous benefactor has expressed his 

 willingness to contribute a sum of 500?., if required, to 

 supplement the 500/. which the Senate has already voted 

 towards defraying the cost of the Darwin commemoration. 



Prof. Woodhead has been re-appointed as the repre- 

 sentative of the University of Cambridge on the council 

 of the Lister Institute of Preventive Medicine. 



.\t the Congregation on Thursday, May 13, the follow- 

 ing Grace will be offered to the Senate :— That there be 

 established in the University a professorship of astro- 

 physics, and that such professorship be governed by the 

 following rules : — (i) the professorship shall be called the 

 professorship of astrophysics, and shall terminate with the 

 tenure of office of the professor first elected ; (2) it shall 

 be the duty of the professor to promote by research and 

 teaching the study of astrophysics ; (3) the professor shall 

 receive no stipend from the University ; (4) the special 

 board of studies to which the professor shall be assigned 

 shall be the special board for phvsics and chemistry. 



Major P. G. Craigie, C.B.,' will deliver the Gilbey 



