466 



NA TURE 



[February 17, 1910 



The useful and general nature of the work carried on 

 in the West Indies under the direction of the Imperial 

 Department of Agriculture is well exemplified in the re- 

 port presented by the curator of the botanic and experi- 

 ment stations in the small island of Montserrat. Experi- 

 ments have been instituted in connection with the important 

 lime-fruit industry to see what results are attained by 

 clean cultivation. The welfare of the peasants receives 

 attention by the provision of help and guidance in cotton 

 cultivation and by the introduction of improved varieties 

 of tannias and cassava, which form a staple article of 

 food. Further, the possibilities of new products are being 

 put to the test in the experimental plots of the wild bay 

 tree Pimenta acris^ h.-non grasses, and Pilocarpus race- 

 mosus ; the two former yield essential oils, while the latter 

 is a source of the drug pilocarpine. 



With the object of obtaining information regarding the 

 geotropic sensibilities of stalked Basidiomycetes, Dr. F. 

 Knoll carried out a series of experiments with Coprinus 

 stiriacus, which he describes in Sitzungsberichte der kaiser- 

 lichen Akademie der Wissenschaften, Vienna (vol. cxviii. , 

 part v.). A study of the longitudinal growth shows that 

 there is a growing region at the top of the stipe or fruit- 

 ing stalk where intercalary growth, due entirely to 

 extension of the separate hyphje, takes place. The stipes, 

 which in the very earliest stage are ageotropic, become 

 later negatively geotropic. Perception of the stimulus and 

 power of response are manifested by the whole of the 

 growing region. The variation noted in the " reaction- 

 period " is remarkable; while the pileus or cap is young 

 an interval of two hours may elapse between the stimulus 

 and response, but when the spores are ripe this period 

 decreases to a few minutes. 



Dr. Emil Werth contributes an account of the surface 

 features of Kerguelen Island to the Zeitschrift of the Berlin 

 Geographical Society. The paper is, to some extent, an 

 abstract of the author's more complete memoir on 

 Kerguelen published in the report of the German South 

 Polar Expedition, 1901-3 ; it gives an account of the topo- 

 graphy of the island, and discusses its relation to volcanic 

 phenomena, past and present glaciation, and rock weather- 

 ing. 



The December (1909) number of the Bulletin of the 

 American Geographical Society contains an account of 

 some experiments on the artificial formation of deltas, 

 carried out in the laboratory of the geological department 

 of Ohio State University, by Mr. Arthur L. Smith. The 

 experiments produced two general forms of deltas, one 

 with regularly semi-circular outline and one with 

 irregularly lobate outline. It was found that the ultimate 

 form of . the first was determined by the maintenance of a 

 constant or increasing stream gradient, and of the second 

 by the decrease of the gradient of the stream. Pronounced 

 cross-bedding was found to occur only in the fore-set layers 

 of the lobate form, and, to a small extent, in all top-set 

 beds. Experiment confirmed the impression, conveyed by 

 an examination of maps of natural deltas, that " fingers " 

 are merely surface features of the delta margin. The 

 shape of a delta is unaffected by the depth of water or 

 irregularities in the bed on which it is formed. 



The Kelvingrove Museum in Glasgow, which belongs to 

 the Glasgow Corporation, contains a valuable collection 

 of minerals, including the Glen collection, purchased in 

 1896, and the Fleming collection, presented in 1902. The 

 museum is rich in the interesting minerals that have been 

 found in the estuary of the Clyde and at other localities in 

 NO. 2103, VOL. 82] 



western Scotland. A useful guide to the minerals in this 

 museum has been written by Mr. P. MacNair, the curator 

 of the natural-history collections (Glasgow : Robert 

 Anderson, 1910, price 3d.). More than half the work is 

 taken up with an introduction to mineralogy, which is 

 more technical and advanced in its treatment than corre- 

 sponding guides issued by other museums. It endeavours 

 to carry the reader farther into the details of crystallo- 

 graphy than most visitors to an English museum wsuld 

 care to follow, and the index includes many names of 

 little importance ; thus in P are Paulite, Pissophanite, 

 Plinthite, and Protheite. The guide concludes with a 

 brief account of the chief mineral species. It is illustrated 

 by a plate of the interesting calcite pseudomorphs, 

 attributed to Gaylussite, that have been dredged from the 

 Clyde estuary. 



Statistics of aeronautical patents in recent years are 

 given by Dr. W. A. Dyes in the Zeitschrift fiir 

 Liiftschiffahrt for February. The number of complete 

 patents granted in Germany was 73 in 1909, 36 in 1908, 

 27 in 1907, 14 in 1906. The corresponding numbers of 

 provisional protections were 140, 48, 37, 14. In view of 

 the fact that in Germany applications for patents are not 

 published until the Patent Office has examined their 

 validity, the_author gives for comparison the number of 

 applications filed by the English Patent Office in the same 

 years, namely, 776 in 1909, 224 in 190S, 189 in 1907, 43 

 in 1906, and 19 in 1905. 



No better illustration of German progress in aerial 

 navigation could be found than the long list of local aero- 

 nautical societies the official notices of which appear in 

 the German Zeitschrift fiir Luftschiffahrt. In addition to 

 the German Luftschiffer Verband, we have " Vereine fiir 

 Luftschiffahrt " for the following districts : — Berlin, 

 Central Rhenish, Lower Rhenish (sections at Bonn, 

 DUsseldorf, Krefeld, Essen, Wupperthal), Pomeranian, 

 Bremen, Bitterfeld, Lower Saxon, Brunswick, Hamburg, 

 Saxo-Thuringian (with sections for Thuringian States, 

 Erfurt, and Halle), Breisgau, Frankfurt, Anhalt. The 

 Imperial Aero Club also occurs in this list, which is 

 based on the February number. We have nothing to 

 correspond with these local societies in England. It must, 

 however, be admitted that the hideous and gruesome 

 illustration of " The Aeronaut's Death " in the January 

 number of the Deutsche Zeitschrift is a little out of place 

 in a scientific journal. 



Dr. F. W. Edridge-Green read a paper on colour- 

 blindness at the Royal Society of Arts on February g. 

 The paper is an excellent and lucid e.xposition of his well- 

 known views upon the subject, and as such it will well 

 repay perusal. In its general character his theory is one 

 which is attractive to physiologists, but some of his 

 assumptions require more impeccable evidence than is 

 adduced. We may cite as an example the statement that 

 " the decomposition of the visual purple by light chemically 

 stimulates the ends of the cones (very probably through 

 the electricity which is produced)." His strictures of the 

 tests for colour-blindness in common use have at least 

 sufficient foundation to demonstrate the need for their re- 

 consideration as a part of the reformation of the official 

 examinations. 



The November (1909) number of the Bulletin of the 

 Bureau of Standards contains a paper, of nearly fifty 

 pages, on platinum resistance thermometry at high tempera- 

 tures, by Messrs. C. W. Waidner and G. K. Burgess. 

 They find that temperatures determined on the pure 



