November i8, 1920] 



NATURE 



389 



reasons, and the great majority of the destitute can- 

 not become independent farmers, but must work for 

 wages. Native labour is cheap, and so forms an 

 obstacle. A policy of segregation of the races in 

 different parts of South Africa is almost impossible 

 iconomically. The address closed with an aphorism : 

 A country will, in the end, belong to the people 

 who do its work." 



An evening lecture was delivered by Prof. J. A. 

 Wilkinson on "The Nitrogen Problem." The South 

 Africa medal and grant were awarded to Prof. E. 

 Warren. 



It is only possible to notice briefly a few of the 

 many papers read before the various Sections, but 

 most of them will be printed in the Journal of the 

 .Association. 



In Section .A, Prof. P. G. Gundry read an interest- 

 ing paper on the effect of high temperature and the 

 elevation of aerodromes in the taking-off of aero- 

 planes. Prof. W. N. Roscveare contributed a short 

 note on Einstein's planetary equation. Father Goetz 

 wrote on rainfall and barometric variation in Bula- 

 w.'iyo. 



Sics,!,. A. M. .Macgregor, H. B. Maufe, and 

 A. J. C. Molyncux contributed papers on the geology 

 of Southern Rhodesia to Section B. Mr. G. N. 

 Blackshaw investigated magnesia-impregnated soils, 

 .ind concluded that the most economical treatment for 

 them was liberal dressings of kraal manure. .Such 

 -.oils occur in the Great IJyke of Southern Rhodesia. 

 Mr. E. V. Flack has analysed samples of bat guano 

 deposits in Rhodesia. They varv in composition, but 

 often the .iddition of sulphate of potash or nitrate of 

 soda or superphosphate greatly adds to their value 

 as fertilisers. 



Dr. P. van der Bijl contributed a monograph on 

 the Polyporea of South .Africa to Section C. Prof. 

 I>. Thoday described the cricoid leaves of the Maquis 

 of the Cape Peninsula, and Mrs. Thoflav gave an 

 .icrount of the seed oi Onetunx Unenion. Dr. E. Marion 

 De)f discussed the distribution of accessory food- 

 factors In plants, and Dr. T. R. .Sim read a naper 

 on South .\frican <erns. Mr. A. O. D. Mogg 



described an interesting method of veld estimation by 

 counting plants in transects, while Prof. S. Schonland 

 discussed certain Crassulaceae found in Rhodesia. 



Papers on the causation of "' lamziekte " were con- 

 tributed to Section D by Sir Arnold Theiler, and from 

 another point of view by Dr. E. R. Hartig. The 

 former has found that bone-meal satisfies the abnormal 

 craving exhibited by cattle suffering from the disease, 

 and farmers in "lamziekte" areas, such as arourKl 

 Vryburg, are bein^r advised to add bone-meal to the 

 ! rations of their infected cattle. Dr. Annie Porter 

 described the life-history of the .\frican sheep and 

 cattle fluke, Fasciola gigantica, and exhibited speci- 

 mens. .She has proved experimentally that the inter- 

 mediate host is the snail, Limnaea natalensis, in 

 which the voung stage, Ccrcaria pigmentosa, occurs. 

 Prof. H. fi. Fanlham gave an account of his lon- 

 tinued observations on various parasitic protozoa 

 found in South .Africa. He has shown that there is 

 a seasonal variation in the occurrence of the spores 

 of Sarcocystis tenella. Mr. J. Sandground contributed 

 an interesting paper on the economic importance of a 

 study of Nematodes, mentioning his researches on 

 Heterodera radicicola. Mr. S. H. Skaife described 

 a Tachinid parasite of the honey-bee. 



In Section E, Mr. N. H. Wilson, of the Rhodesian 

 Native .Affairs Department, gave a paper on the future 

 of the native races there, and considers that it is 

 necessary to allow both white and black to make 

 full economic use of their abilities with the w-hite 

 man as a directing and predominant partner. The 

 Rev. H. .A. Junod, in describing some features in the 

 religion of the Ba-Venda, mentioned that they have 

 two sets of religious institutions, ancestor worship and 

 a vague monotheistic notion. The Rev. W. .\. 

 Norton descril)ed some of his ethnological and lin- 

 guistic studies in Bcchuanaland. 



.A paper on agricultural economics bv Prof. R. .\. 

 I^hfeldt, and one on geographical method by Mr. ]. 

 Hutcheon, were contributed to .Section F. 



Johannesburg is now the seat of the headquarters 

 of the .Association, and the next meeting will be held 

 at Durban in July, 1921. H. B. F. 



Geography at the British Association. 



A FTER the presidential address by Mr. J. Ma<- 

 ■^*- farlane the prcKecdings of Section E began with 

 .1 paper by Mr. D. Lleufer Thomas on some geo- 

 graphical aspects of the distribution of population on 

 the South Wales coalfield. The main coalfield of 

 South Wales comprises about 780 square miles. It 

 ' chiefly an elevated plateau with an average altitude 

 f 1000 ft., rising in North (jlamorganshire to some 

 •000 ft., and is deeply scored by narrow-, declivitous 

 . .illeys. Th<-.sc valleys open by narrow gaps to the 

 ' oastal plain. The result of these conditions is that 

 ihe population, which is mainly dependent on the coal 

 iitcrops, is [x-nt up in the valleys and somewhat 

 • moved from the outer world. .Anotfjer determining 

 factor in the location of population was the occurrence 

 near tlv coal of raw materials valuable in manufac- 

 tures, such as iron, or sites offering special facilities 

 for the assembling and treatm<'nt of imported 

 "i.iterials. such as .S«||S)nsea, which attracte<l the 

 •pper of Cornwall. Until nearly the middle of tfw 

 ineteenlh century coal-mining was entirely subsidiarv 

 • iron-making, and the development of the roa\fK'\d 

 > ns tfiereforc confined to its outer fringes, leaving the 

 hole of the interior as sparsely populated as in tlw 

 — I .,,,p Development gradually spread south- 



2664, VOL. io6] 



wards from the iron centres down the valleys. Tl»e 

 present congestion of population is of comparatively 

 recent date. The population is recruited mainly from 

 tfie West Midland Counties, especially the British 

 district, and to a less extent from tl-H* south-western 

 counties. .As a result, Monmouthshire and, to a less 

 degree. East Glamorg.mshire have l)een anglicised in 

 .speech. !n the discussion following the paper Mr. 

 n. J. Randall emphasised the transitory nature of 

 the population referred to and its complete dependence 

 on coal production and demand. 



Dr. .A. E. Trueman read a paper on the iron 

 industrv of South Wales. Th«' distribution of the 

 industry was determined by the working of ironston<> 

 nodules, which are richest in the eastern part of the 

 coalfield. Loral hiemalitic ores have had little effect 

 on the industry. The ironstone nodules were originally 

 collected in stream-beds and worked chiefly along the 

 northern outcrops, where the dip is less steep than in 

 the south. With the deforestation of the country- 

 smelting derlinod. but revived in the nineteenth cen- 

 turv with the use of coal. The phosphatic nature of 

 the nodules rendered them unsuitable for the manu- 

 facture of steel bv early processes, and the output of 

 local ore gradually decreased. At present it is only 



