May 6, 1909] 



NATURE 



287 



Three parts of the " Palaeontologia Indica," just received 

 from the Geological Survey of India, contain important 

 memoirs on the Lower Mesozoic invertebrate faunas of 

 the Indian region. A collection of fossils, chiefly bivalved 

 shells, obtained by Messrs. T. D. La Touche and P. N. 

 Datta from the Napeng beds of the Northern Shan States 

 of Burma, is described by Miss Maud Healey, who shows 

 the fauna to be remarkably similar to that from the 

 Rhastic formation of Europe. Even the characteristic 

 Avicula contorta occurs. The fossils, however, are much 

 distorted, and preserved only as imperfect casts, so that 

 their exact determination is almost impossible. Miss 

 Healey remarks that very similar bivalves have also been 

 found in rocks on the west coast of Sumatra which are 

 not Eocene, as hitherto supposed, but really of Rheetic 

 age. New collections, chiefly of Cephalopoda, from the 

 Trias of Spiti, in the Himalayas, are described by Prof. 

 Carl Diener, who makes an interesting contribution to our 

 knowledge of this much-discussed formation. He treats 

 especially of the Upper Muschelkalk, and compares in 

 detail the several zones with those recognised in Europe. 

 A remarkable collection of fossils from scattered blocks of 

 Upper Triassic and Liassic age, found in the frontier dis- 

 trict between Hundes and Malla Johar, is also described 

 by Prof. Diener. Basing his studies chiefly on ammonites, 

 he concludes that " the difference between the Liassic faunse 

 of Wiirtemberg or England and the Alps is more con- 

 spicuous than that between the Mediterranean and Tibetan 

 faunae of the Lower Lias." 



Mr. B. Gomme recently issued the " Index of Archaeo- 

 logical Papers published in 1907," which forms the 

 seventeenth annual number of this publication, originally 

 started by his father, Mr. G. L. Gomme. It contains 

 references to the proceedings of fifty-two learned societies 

 in Great Britain and Ireland, and is likely to be useful 

 to all who are interested in archaeology. Many societies 

 are subscribers to this index, which they issue with their 

 annual Proceedings, a course which may be safely recom- 

 mended for general adoption. This publication would be 

 of much more practical value if, in addition to the bare 

 titles of communications, a short abstract of the contents 

 or a summary of the views advocated by the author were 

 appended. 



In the April number of Man Mrs. M. E. Cunningham 

 directs attention to a remarkable feature in the entrench- 

 ment known as Knap Hill Camp, in Wiltshire. Along the 

 exposed side of the camp the entrenchment is pierced by 

 no fewer than six openings or gaps, which were formerly 

 supposed to be cattle-tracks or made for agricultural pur- 

 poses. Excavations, however, show that none of them is 

 the result of wear or accident, and that they represent 

 gangways intentionally left in the circumvallation. Some- 

 thing of the same kind was remarked by General Pitt- 

 Rivers at Winkelbury Camp, and he supposed that they 

 were gangways adapted to allow in an emergency a con- 

 siderable number of cattle to enter the camp. In this 

 case, Mrs. Cunningham urges that it would have been 

 simpler to make one or two wide entrances. From the- 

 fact that these causeways lie askew to the gaps in the 

 rampart she suggests that they may have been purposely 

 left as positions from which the defenders could enfilade 

 the ditch, the distance from one causeway to another being 

 not greater than could be covered by hand-thrown missiles. 

 It is to be hoped that the fuller exploration of the site 

 which the writer promises will throw further light on the 

 interesting problems connected with prehistoric fortresses 

 whicli are raised in this communication. 



NO. 2062, VOL. 80] 



The report of the Danish Meteorological Institute on the- 

 state of the ice in the Arctic seas during igoS shows that 

 the general distribution of the Polar ice was almost the 

 opposite of that observed in the preceding year. During 



1907 greater masses of ice than usual drifted from the- 

 Arctic Ocean towards Franz Joseph Land and Spitsbergen 

 and along the east coast of Greenland, whereas during 

 igoS those regions were more approachable and free from 

 ice than is normally the case. The supposition that the 

 change was due to the ice having found an outlet else- 

 where is supported by the fact that the ice conditions were 

 reported as specially unfavourable in the Bering and 

 Beaufort Seas. 



The meteorological and magnetical report of the Royal 

 Cornwall Polytechnic Society, containing the observations 

 made at Falmouth during 1908, has been received. This 

 important observatory receives an annual grant of 250J. 

 from the Meteorological Committee for the supply of hourlv 

 meteorological observations, and is at present subsidised 

 by the Royal Society and British Association for the main- 

 tenance of magnetic observations. At the request of the 

 International Conference on Terrestrial Magnetism it 

 supplies a table of the daily magnetic records to the Royal 

 Netherlands Institute for publication with similar data 

 from other observatories ; the magnetic results are also 

 published by the National Physical Laboratory. A com- 

 parison of the air- and sea-temperature observations for 



1908 shows that the mean of the latter (52 9°) was i-s" 

 above that of the air ; from May to July inclusive the 

 mean sea temperature was lower than that of the air. 

 The rainfall amounted to 37-6 inches, being 4-4 inches 

 below the average. A chart is added to the report show- 

 ing the annual rainfall for thirty-seven years, 1872-1908, 

 registered by the self-recording rain-gauge ; the wettest 

 year was 1872, rainfall exceeding 64 inches, and the driest 

 1887, rainfall less than 30 inches. The mean magnetic 

 declination for the 3'ear was 17° 54' W. 



Mr. S. S. Buckman has sent us a copy of a paper 

 (Oxford : Parker and Son) in which he advocates a scale 

 of notation with radix 8 instead of lo. His proposals are 

 more revolutionary than this change necessarily implies, 

 for he would write the numerals upside down, and com- 

 pletely alter his weights, measures, and coinage down to- 

 a charge of 7jd. for telegrams. Apart from the object- 

 lesson that in Austria even the change from kreuzer to 

 heller took years to accomplish (and kreuzer are probably 

 not dead yet), we note that the advantages of " octonary 

 numeration " were clearly and plainly set forward, with- 

 out the introduction of unnecessary complications, by Prof. 

 Woolsey Johnson in October, 1891 (Bulletin New York 

 Mathematical Society, i., i). 



The importance of the discovery made by Prof. Towns- 

 end last year, that when a gas is ionised by Rontgen rays 

 positive ions are produced having double the electric 

 charge previously regarded as the ionic charge, has led" 

 Drs. J. Franck and W. Westphal, of the University of 

 Berlin, to investigate the properties of these doubly charged 

 ions in some detail, and their results were communicated 

 to the German Physical Society on March 5. They find 

 that the mobility of the ions in an electric field, as 

 measured by a modification of Zeleny's method, is identical" 

 with that of the singly charged ions, while their rate of 

 diffusion, as measured by a method identical in principle 

 with that first used by Townsend, is only half that of the- 

 singly charged ions. The double charge is thus accom- 

 panied by double mass, and the number of double ions 

 produced by Rontgen rays is, the authors find, only about 

 9 per cent, of the total number of positive ions. 



