228 



NATURE 



[December 14, 191 1 



petal colour, all of which received quantitative measure- 

 ment, together with qualitative studies of the dehisc-nc*' 

 of the fruit and the hairiness of the ovary walls. Tin- 

 article is illustrated by two photographs, and by ten 



riy a hundred frequency 



diagrams which include nearly 

 polygons. 



W. L. B. 



I 



AMPHIBIAN FAUNAS OF SOUTH AFRICA 

 AND MADAGASCAR. 



N discussing the relationships between the amphibian 

 faunas of South Africa and Madagascar in the Annals 

 of the Transvaal Museum for April, Mr. J. Hewitt accepts 

 the theory of an early land connection between Australia, 

 India, Madagascar, the Seychelles, and South Africa, 

 which was sundered between Australia and Africa after the 

 Lower Cretaceous, and was elsewhere broken up into 

 islands in the early Tertiary. The connection between 

 Madagascar and India persisted until the Eocene, or 

 perhaps later, as an archipelago, and Africa may have 

 been connected by swamps with Madagascar until the early 

 Pliocene. Another land-bridge connecting South Africa 

 and South America by way of the Atlantic is likewise 

 accepted. The fauna of the whole area is considered to 

 have had many features in common ; but after the separa- 

 tion of Madagascar and the formation of the African con- 

 tinent the latter area was invaded by a Pala;arctic fauna, 

 which could not reach Madagascar. The fauna of that 

 island accordingly seems to represent in a modernised form 

 — with a few additions — the one originally common to the 

 southern Ethiopian area. 



The author then proceeds to discuss how the rela- 

 tions of the amphibian faunas of Africa, Madagascar, 

 South America, and Australia can be explained on 

 these suppositions. To follow him in detail would 

 take too much space ; but it may be mentioned 

 that he is disinclined to accept the generic identity 

 of the Malagasy boa-like snakes with South American 

 types, and that he regards true frogs (Rana) as of African, 

 and tree-frogs (Hylidae) as of South American, origin. 

 The two latter are stated to have attained their present 

 distribution by crossing what is now Bering Strait, in 

 opposite directions, after the sundering of the connection 

 between Africa and South America (p. 37), Rana having 

 thus reached South America from the north (p. 35). On 

 the other hand, it is stated later (p. 38) that the Ranida 

 are an Old World group " which crossed over to the Neo- 

 tropical region at a time when the land-bridge was jusl 

 beginning to give way, and when eventually they had 

 travelled northwards as far as the Antillean' bridge this 

 was no longer complete." The discrepancy in the two 

 statements requires explanation. 



WATER M I'l'I.V I.\ AISIRAUA. 

 'pHE great drawback to settlement in some parts of 

 Australia is the frequent droughts that have to be dealt 

 with. So far back as 1884 the New South Wales Govern- 

 ment appointed a commission to consider the question of 

 irrigation, and, as a result, a water conservation depart- 

 ment was organised, and an experienced Indian irrigation 

 engineer appointed to advise. As one result of this the 

 construction of a dam across the Murrumbidgee River was 

 decided on. This dam, known as the Burrinjack Dam, 

 rivals in size and quantity of water impounded the famous 

 Assouan Barrage across the Nile. The Murrumbidgee 

 Kiver for 200 miles above the dam runs its course prin- 

 cipally amongst mountains, the higher peaks of which are 

 covered with snow in winter. The catchment area at this 

 point amounts to 5000 square miles, the rainfall varying 

 from 20 to 70 inches a year. At the place where the dam 

 has been constructed the whole of the river water passes 

 through a narrow granite gorge, and consequently the 

 mmimum cost of construction, combined with the "maxi- 

 mum stability, has been secured. For about 200 miles 

 below the dam no irrigation works are needed, as the 

 distn^ through which the river flows is undulating and has 

 a sufficient rainfall. Below this the river enters a flat 

 country, with a diminished flow of water. Like some other 

 rivers in Australia, the Murrumbidgee, instead of increasing 

 in volume as it proceeds on its downward course to the 

 NO. 2198, VOL. 88] 



ocean, actually diminishes, and becomes a small stream 

 This is due to the diversion of its water into shall' < 

 lagoons, where the evaporation caused by the fierce si 

 and percolation disposes of the greater part of the •• •■• 

 The dam is of concrete, 240 feet high and 784 fe< 

 It will back up the water in the main stream for 41 

 and of two of its tributaries for 15 and 35 miles. Althuu. 

 the water supply is to be brought into operation at or.- 

 the dam has only been built up to 110 feet; the rem 

 130 feet, it is expected, will take two years more t 

 plete. For carrying on the works and providing f 

 staff employed a temporary township has been 

 provided with complete sanitary arrangements and n. ; 

 attendance. An electric installation has also been set up | 

 for working the cranes and other machinery. A light ■ 

 railway 28 miles long has been constructed connecting t' 

 temporary township with the main line of railway fri' 

 Sydney to Melbourne. The estimated cost of this wot 

 is 758,000/. 



THE DIVINING ROD. 



"T^R. L. WEBER, professor of physics in the Univcrsi 

 of Kiel, has published in the Journal fiir Gasbrhufi 

 ung und Verwandte Belcuchtungsarten sowie fiir H 

 versorgung a copy of an address on the divining re 

 i by him at Flensburg in September last. Dr. Weber regai 

 belief in the powers of water diviners as a form of an 

 quated superstition and gross error ; he is of opinion tl: 

 there is no evidence that the movements of the rod :■. 

 due to any cause outside the diviner, who is the subject 

 self-deception. He bases this view on the results of carr f 

 investigation, but, in so far as the paper in question 

 concerned, only one instance of actual experiment is giv> 

 (see below). 



Dr. Weber mentions the results obtained by Herr vi 

 L'slar in the German African colonies, and thinks that '.'. 

 divining rod was, in this case, simply a magic staff ■ *- 

 animated von Uslar's expedition to extraordinary ex' 

 and, more particularly, to deep boring with €\^... 

 results. 



The experiment mentioned in the Journal is one p' 

 formed at Flensburg before the Association of Gas ar 

 Water Specialists of Lower Saxony. Herr L6on, a w< ' 

 known water diviner from Kiel, submitted himself to ti. 

 blindfold test tried so frequently; he indicated two places ir 

 a room, in one of which his rod acted strongly, and in the „ 

 other of which there was little or no action. He was then 

 carefully blindfolded, turned round, and taken to the two 

 places in irregular turns, when his rod gave corresponding 

 indications to those obtained at first (when not blindfolded) 

 in only two cases out of the six. The present writer has 

 performed similar experiments, and always with similar 

 results to those which Dr. Weber obtained with Herr Leon ; 

 he is, however, of opinion that they cannot be regarded as 

 conclusive, since it is quite possible that, if the movements 

 of the diviner's rod are due to an objective cause, the 

 blindfolding may influence the nervous condition of th«* 

 water diviner in such a way as to render him a In- 

 efficient " water indicator " than he would be in ordin.T 

 circumstances. On the other hand, it must be remember 

 that Herr L6on accepted the conditions of the experimer. 

 and when a scientific man undertakes to investigate .- 

 apparently mystic process, such as water finding, he cann. 

 be expected to do more than lay down conditions whit 

 appear to him reasonable and are accepted by the diviner. 



J. W. 



NEW MECHANICAL ENGINEERING LABORA- 

 TORY OF THE MUNICIPAL TECHNICAL 

 INSTITUTE, BELF.iST. 

 y^ BOUT eighteen months ago the Corporation of Belfa- 

 authorised the preparation of plans and the install, 

 tion of a teaching equipment suitable for the scientific 

 training of mechanical engineers. The plans for this work 

 were at once put in hand, and the installation has been 

 carried out to the designs and under the direction and 

 superintendence of Prof. J. H. Smith, head of tb» 

 mechanical engineering department of the institute. 



