450 



NATURE 



[December i, 192 i 



read, viz. by the Rev. J. CuUen in connection with 

 prime numbers, by Dr. F. E. Hackett on a problem 

 in relativity, and by Prof. D'Arcy Thompson on the 

 properties of the tetrakaidekahedron. 



In the afternoon Prof. A. S. Eddington delighted 

 a very large audience with a semi-popular lecture on 

 Einstein's theory of relativity. 



On the last day of the sectional meetings (Sep- 

 tember 13) the chief business was the joint discus- 

 sion with Sections C, D, and K on "The Age of the 

 Earth," already reported separately in Nature 

 of October 13 (p. 217). There followed several 

 papers of astronomical interest, including "The 

 Microchronograph," by Prof. R. A. Sampson; "The 

 Magnetic Storms of the Present Solar Cycle," by 

 the Rev. A. L. Cortie; and "Discussion of the Radial 

 Velocities of Stars," by Prof. G. Forbes. Earlier in 

 the meeting also Sir Frank Dyson had given an 

 account of the results obtained with the 72-in reflector 

 in British Columbia. 



As already mentioned, it was frequently necessary 

 for a sub-section of cosmical physics to meet 

 separately. In this sub-section Dr. A. Crichton 

 Mitchell described the new geophysical observatory 

 recently established in the Shetlands by the Meteoro- 

 logical Office, Air Ministry, for research on problems 

 of terrestrial magnetism and electricity, and particu- 

 larly work on aurora. Under the title "The Mag- 

 netic Anomaly in the District of Kursk, Russia " 

 Prof. A. Kriloff gave an account of the unusually 

 large observed variations of the magnetic elements in 

 the region indicated. Capt. C. K. M. Douglas and 

 Dr. H. Jeffreys, in papers entitled respectively "Some 

 Remarks on Bjerknes's Theories of Cyclones and 

 Anticyclones" and "The Cause of Cyclones," 

 discussed the dynamical and physical condi- 

 tions relating thereto. Mr. W. H. Dines, in 

 some remarks on "The Discontinuity of Tempera- 

 ture at the Top of the Troposphere," suggested that 

 it might be due to the very gradual sinking and 

 spreading out in higher altitudes of air which had 

 entered the stratosphere in tropical regions. Dr. 

 Hans Pettersson read a paper on " Internal Move- 



ments in the Sea," in which he explained, and illus- 

 trated experimentally, the influence of the wind on 

 the vertical displacements of strata of different 

 salinity, temperature, density, and biological charac- 

 teristics off the west coast of Sweden, together with 

 the associated inflow of freshly saturated sea-water 

 through the straits leading to the Baltic. In a paper 

 on "The Dry Period of 192 1 in England and Wales" 

 Mr. M. de Carle Salter gave interesting statistics 

 relating to the amount and distribution of rainfall 

 during the recent drought. 



An extensive exhibition of diagrams and photo- 

 graphs of meteorological interest, arranged in con- 

 nection with the Edinburgh meeting of the Royal 

 Meteorological Society, remained open for British 

 Association members. In addition. Dr. Crichton 

 Mitchell exhibited a series of autographic records 

 from the Eskdalemuir Observatory, embracing mag- 

 netograms, electrograms, and Galltzin selsmograms. 

 Diagrams showing the diurnal variation of atmo- 

 spheric pollution in normal conditions, during fog, | 

 and during the coal strike were shown by Dr. J. S. 

 Owens. 



During the meeting a branch of the Meteorological! 

 Office, Air Ministry, was established In connection! 

 with Section A in the Natural Philosophy Depart-l 

 ment of the University, and a wireless receiving set! 

 for the reception of data was sj>eclally Installed there' 

 by the Communications Department of the Air 

 Ministry. The programme outlined In Nature of 

 September 8 (p. 44) was carried out, and a daily 

 weather report produced and exhibited in many public 

 places In Edinburgh ; while those visiting the rooms 

 of Section A could see on a large blackboard the 

 latest synoptic chart of the weather over an area 

 extending from Spitsbergen southward to the North 

 African coast and from the Azores and Iceland east- 

 ward to the Russian frontier. Meteorological and wire- 

 less officers were In attendance, who demonstrated to 

 many Inquirers the reception by wireless of the 

 meteorological data Issued several times daily by 

 European countries, the subsequent charting, and the 

 production of the weather report. 



The Ethnology of the Sudan. 



A THIRD ethnographical expedition, under the 

 -^*- direction of Prof. C. G. Seligman, Is being sent 

 out by the Sudan Government with the object of inves- 

 tigating the tribes of the Mongalla province, particu- 

 larly those along the east bank of the Nile. Prof, and 

 Mrs. Seligman will be joined at Khartum by Mr. S. 

 Hillelson, of the Gordon College. The peoples to be 

 studied Include the Bari, the Ascholl, the MadI, and 

 the Latuka, and, If time permits, a trip into the old 

 Lado enclave will be undertaken. 



Scarcely any ethnographical Information concerning 

 the Latuka has been forthcoming since the time of 

 Sir Samuel Baker (182 1-1893), and little Is known of 

 them beyond the fact that thev are ruled by their 

 hereditarv rain-makers, whose ceremonies for drawing 

 down rain have been described. The Madi may be 

 regarded as an entirely unexplored ethnic and cultural 

 field. 



The Ascholl are of especial interest, since they spenk 

 the Shilluk language, but are known not to share the 

 Shilluk religion ; Indeed, they do not even know the 

 name of Nyakang. Our knowledge of the Shilluk 

 peoples is derived from the reports of the two previous 

 expeditions undertaken for the Sudan Government by 

 Prof. Seligman. In the winter of 1910 the inhabitants 

 of the banks of the Whlt^ Nile and the Nubas of 



NO. 2718, ^OL. 108] 



southern Kordofan were visited, and in 191 1-12 the 

 desert Arabs In the region of the Kordofan-Darfur 

 border and the Hammites of the Red Sea Province. 



The Shilluks are a pastoral people numbering about 

 40,000 who live along the White Nile south of Fashoda 

 and up the Sobat River. Their religion is chiefly 

 king-worship. Their king is believed to be a re- 

 incarnation of the semi-divine founder of the dynasty, 

 Nyakang, who is related to the great immanent 

 creator Juok. Juok Is worshipped only through 

 Nyakang, who Is the rain-giver of a land where Irriga- 

 tion Is not practised. In his reports to the Sudan 

 Government Prof. Seligman described the rain-making 

 and harvest ceremonies of this people, as well as the 

 process for transmitting the spirit of Nyakang to a 

 new king. The reigning monarch is put to death on 

 the first indication of failing powers, usually between 

 the ages of fortv and fifty, and a prince is chosen 

 as his successor. " The men' of Akurwa bring from the 

 shrine to the village of Kwom, near Fashoda, a sacred 

 four-legged stool and an object bearing the name of 

 Nvakang himself, which is "believed to be a cylinder 

 or a rude image. At Kwom the king-elect and his 

 chiefs engage in a mock fight with the bearers, who 

 are permitted to win, and escort the king to Fashoda. 

 .-Vfter a brief sojourn within the shrine the sacred stool 



