2^8 



NATURE 



fApRii. 28, 1910 



strong point about Ameghino's spirited and persistent 

 defence is that he now makes it clear that he has studied 

 thin sections of the earths and of numerous artificially 

 prepared products. It is admitted on all hands that 

 minerals from decomposed lavas abound in the Pampas 

 earths, and thus- would occur undestroyed in the products 

 of their partial fusion. This was pointed out in the 

 previous notice in Nature, and the thoroughness of 

 Ameghino's reply is shown by his references to this notice, 

 and his correction of some of its statements, in his 

 " Examen critique du M^moire de M. Outes " {Anales del 

 Mtis. Nac. de Buenos Aires,. 1909, p. 459). While Ducloux, 

 and perhaps our own reviewer, seem allowed some saving 

 grace, the work of Outes is said to contain " des h6r^sies 

 scientifiques tellement colossales que personne ne peut croire 

 qu'il les ait publi^es de bonne foi." A paper issued on 

 January 29 (ibid., tomo xx., p. 39) provides a very useful 

 summary, with long quotations, of previous work on these 

 debatable earths down to 1907, and a bibliography of work 

 from 1907 to 1909. 



Three new species of Echeveria from southern Mexico 

 are described and figured by Drs. J. N. Rose and C. A. 

 Purpus in vol. xiii., part ii., of the Contributions from 

 the United States National Herbarium. It is suggested 

 that, two, E. gigantea and E. subalpina, will be found 

 useful in horticulture as bedding plants. 



Botanists who are contemplating a summer holiday in 

 the Alps with the view of collecting choice plants will be 

 interested in two articles by Mr. H. S. Thompson, pub- 

 lished in the Gardener's Chronicle (April 16 and 23), 

 giving an account of the flora of Mont Cenis. Among the 

 plants taken between Susa and the Hospice were Tele- 

 phitim Imperati, Cytisus supinus, Dianthus neglectus, 

 and Saponaria lutea. Around the small Lac Clair, a 

 wonderfully rich hunting ground, situated at a height of 

 9000 feet, the author found Campanula cenisia, Arabis 

 coerulea, Cortusa Matthioli, and clumps of Saxifraga 

 biflora. Altogether Mr. Thompson collected 180 plants 

 growing above an altitude of 8000 feet, besides meeting 

 with a rich flora at lower levels. 



A CURIOUS gall on the Indian grass Ischaemum pilosum 

 is described by Mr. L. A. Boodle in the Kew Bulletin 

 (No. 3). It takes the shape of a cj'lindrical tube about 

 15 cm. long, resembling a slender goosequill, which, with 

 a few scale leaves at the base, arises as an erect branch 

 from the creeping rhizome. The gall caused by an insect, 

 Oligotrophus ischaemi, is considered to be a greatly 

 elongated internode. Various illustrations are given, in- 

 cluding figures of the transverse section of the solid normal 

 and hollow modified stem. Reference is also made in a 

 short note to a method of preparing baobab trees as water 

 reservoirs in the Soudanese province of Kordofan. The 

 trunk is hollowed out to form a cistern about 20 feet 

 deep and 10 feet in diameter ; then a shallow basin is 

 prepared round the base of the tree for the collection 

 of water during the rain, from which it is transferred 

 to the hollowed trunk. 



The annual report for 1909 of the Rothamsted Experi- 

 mental Station is not so adverse as might have been 

 expected considering the heavy rainfall and the low 

 temperatures that prevailed through the summer. The 

 yield and quality of wheat grain was poor, but the yields 

 of barley and mangolds were above the average. A com- 

 parative test of nitrate of lime, cyanamide, nitrate of soda, 

 and sulphate of ammonia, together with superphosphate in 

 each case, was initiated with barley as the crop, which 

 NO. 21 13, VOL. 83] 



has yielded, so far, no practical difference in the results. 

 The important investigations carried on by members of 

 the staff in connection with the effect of partial sterilisa- 

 tion of the soil, the direct assimilation of ammonium salts 

 by plants and the development of the wheat grain have 

 already formed the subject of a reference in these 

 columns. 



The annual report for 1909 of the Woods and Forests 

 Department of South .Australia appears in Nos. 4 and 6 of 

 the Agricultural Journal of that colony, and shows that 

 the possibilities of the situation are being realised. It is 

 said that inquiries have been made from America for one 

 million railway sleepers cut from red-gum ; the contract 

 could not be taken up, because the supply of red-gum for 

 sleepers is rapidly being used up for Australian railways, but 

 it is of interest as showing that even the United States 

 are having to look about for timber supplies. The expendi- 

 ture of the Department has been increased from 10,080/. 

 to 17,575/. ; the intention is to encourage in every way the 

 planting of pine, gum, and other trees, even to consider 

 the advisability of offering a bonus sufficient to cover the 

 cost of the necessary attention to the trees for the first 

 four or five years of their existence. Wasteful methods of 

 handling mature timber are still in vogue; we are told 

 that only about one-third of the timber on any given area 

 is properly utilised, the rest being destroyed by axe and 

 fire owing to the unsystematic and wasteful character of 

 the lumbering operations. 



The marked increase of the sensitiveness of an instru- 

 ment for detecting alternating currents of electricity when 

 the free period of the instrument coincides with the period 

 of the current was pointed out by Prof. M. Wien twenty 

 years ago. The property has since led to the production 

 of several forms of vibration galvanometer, and the theory 

 of the instrument has to some extent been investigated. 

 .\ more complete examination of the theory, and a com- 

 parison of the theory with the actual behaviour of three 

 forms of the galvanometer, are to be found in a paper 

 on the subject by Mr. F. Wenner in the February number 

 of the Bulletin of the Bureau of Standards. A few new 

 hints as to the design of the instruments are also given. 

 In order to avoid giving the instrument a double period 

 the moving system must be symmetrical. In bridge work 

 the resistance of the galvanometer should be very much 

 less than that of the bridge, and the back electromotive 

 force developed in the instrument should be half that 

 impressed on the galvanometer circuit. 



The Jesuit Fathers at Zikawei are to be congratulated 

 on the addition to their observatory of a seismological 

 station. During the months of January and February this 

 year a Weichert pendulum of 1200 kilos, recorded twenty- ' 

 six shocks. Twelve of these were also noted by an Omori 

 pendulum of 15 kilos. Both instruments record on smoked 

 paper. The difference in the number of records obtained 

 from these two types of instruments is undoubtedly 

 striking, but had there Jaeen at Zikawei an apparatus 

 which gave a photographic record of earthquake motion it 

 is probable that the total number of shocks noted would 

 have been more than doubled. During this period at 

 Shide, in the Isle of Wight, photographic recorders of 

 the British Association type noted eighty-one disturbances. 

 .-Vn instrument writing on smoked paper at that station, 

 however, only recorded a few of these. 



In the second fascicule of vol. iv. (new series) of the. 

 Annales de I'Observatoire royal de Belgique, the geo- 

 physical results obtained at the observatory during 1908 



