3^o 



NATURE 



[August 9, 1900 



Society on chanp;es in glaciers ; Prof. Zschokke, of Basle, on 

 the fauna of mountain streams ; and Prof. Schardt on the 

 tectonic conditions on the northern slopes of the Swiss Alps. 



A LENGTHY ticatise on that mysterious form of atmospheric 

 discharge known as "globe lightning" appears in the current 

 number of the Annalen der Physik. It is by Prof Max Toepler, 

 the inventor of the Toepler machine and the discoverer of the 

 stratified brush discha>-ge. After comparing all the published 

 records of the phenomenon, he comes to the conclusion that 

 the globe is a form of continuous atmospheric di-charge analogous 

 to the " brush arc discharge" of the laboratory. A lightning 

 flash leaves behind it a track of heated and possibly ionised air, 

 along which a slow continuous discharge passes for some time 

 after the flash has passed. When this continuous discharge is 

 strong enough, any pait of the track which has an exceptionally 

 high resistance may be made to glow, and the gloAf may con- 

 tinue for several seconds or even hilf a minute. The track miy 

 be blown aside by the wind or driven by electrostatic forces, 

 and then the globi will be seen to wander as is usually 

 described. It often finishes with another lightning flash, and 

 the thunderclap following that is described as an "explosion " of 

 the ball. Considering the size and duration of the globe. Prof. 

 Toepler estimates its current strength at something between 

 2 and 20 amperes. Considering that a lightning flash often 

 carries lo.ooo amperes, the destruction wrought by globular 

 lightning should be inconsiderable. 



The uses of monochromatic light in optical experiments are 

 so numerous that considerable interest attaches to the paper, on 

 the means of producing such light, by MM. Charles Fabry and 

 A. Perot in ihQ Journal de Physique for July. After pointing out 

 the disadvantages of sodium light on account of the proximity 

 of the D lines, the authors divide the methods of producing a 

 beam of monochromatic light into two, viz. : (i) simplification 

 of a beam of white light, and (2) use of light emitted by a gas. 

 Under the latter method are included (a) flames ; {b) gases or 

 vapours rendered luminous by electricity ; {c) induction sparks ; 

 and. ((/) the electric arc. In connection with (b), it is found that 

 the quality of the rays depends on the nature of the current ex- 

 citing them, and the authors consider the use of (l) a coil with 

 secondary condenser, (2) alternating currents, (3) continuous 

 currents ; of these methods the last is ihe best, though the second 

 is better than the first. While the results of these investigations 

 cannot be briefly summarised, we notice that the authors have 

 shown the possibility of improving the action of Michelson's 

 tubes, of using a modification of the mercury arc of Arons as 

 a source of monochromatic light of great intensity, of using 

 the rays of a certain number of metals for interference observa- 

 tions where the difference of path is considerable, and, by 

 measuring the wave-lengths, of adding a number of new fixed 

 points on the spectrum. The paper concludes with a table of 

 wave-lengths determined by MM. Perot and Fabry, and com- 

 pared with the determinations of Michelson. 



Stormy and boisterous weather has occurred over the greater 

 part of the British Islands during the past week, and exception- 

 ally heavy rains have been experienced in many districts. On 

 August 3 a storm of unusual severity for the time of year swept 

 across England, and a heavy gale blew over the southern portion 

 of the kingdom, occasioning considerable damage on our coasts, 

 as well as to the fruit and corn in the inland districts. A similar 

 disturbance struck our west coasts on August 6, and although it 

 followed very much the same path as the storm of Friday it was 

 more erratic, both in its track and rate. The storm was heavy 

 again in many parts of England, and further damage to the 

 crops has been occasioned. The temperature has fallen- con- 

 siderably during the last few days, and the weather has been 

 cold for the time of year over the whole country, the mid-day 

 eadings in many places being below sixty degrees. 

 NO. 1606, VOL. 62] 



The new Daily Weather Report, the issue of which was 

 announced in Nature of July 26 (p. 3C0), is now on sale every 

 day at the Meteorological Office and several railway bookstalls 

 in London. The attempt thus made to create an intelligent 

 interest in meteorological records and forecasts is one to be 

 encouraged, but we are afraid that the method adopted is not 

 very attractive. The weather charts are admirable, and in con- 

 nection with the statement of the general situation and the fore- 

 casts they are most instructive. Too much prominence could 

 not be given to these two pages of the Report, which ought to 

 find a place in the hall of every educational institution in the 

 country. But the tabular matter, included in the Report 

 is of too detailed a character to be of public interest, and the 

 Meteorological Council might usefully consider whether it would 

 not be sufficient to publish such statistical information once a 

 week or once a month instead of every day. 



The high kite flight at Blue Hill Meteorological Observatory, 

 of which mention was made a few weeks ago (p. 252), was, Mr- 

 Lawrence Rotch informs us, exceeded on July 19. A line 

 of six kites reached an altitude of 15,900 feet, or three miles and 

 sixty feet, above the sea, which exceeds the highest point ever 

 reached in America by a balloon used for scientific purposes. 

 Prof. Hazen, of the U.S. Weather Bureau, obtained observations 

 in a balloon at a height of 15,400 feet in an ascent from St. 

 Louis in June 1887. This is the highest ascent in America 

 from which observations have been published. Four and three- 

 quarter miles of steel piano-wirewere used at Blue Hill as a flying 

 line. The instruments attached to the kites showed freezing 

 temperature at the highest point and a north-west wind with a 

 velocity of twenty-six miles an hour. The air was found to be 

 exceedingly dry. 



The Proceedings of the Geologists' Association for May con- 

 tains an interesting paper, entitled " The Natural History of 

 Phosphatic Deposits," being an address delivered in February 

 last by the retiring President of the Association, Mr. J, J. H. 

 Teall, F.R.S. The phosphates of igneous rocks and mineral 

 veins are first discussed, and it is pointed out that apatite, the 

 most abundant phosphatic mineral, is the principal source from 

 which the phosphorus of the sedimentary rocks and of organic 

 bodies is derived. Attention is drawn to the points of analogy 

 in the vein-occurrence of apatite and tin-stone. Having shortly 

 described the conditions and causes which bring about the for- 

 mation of modern phosphatic deposits, the author passes in 

 review the principal occurrences of phosphates in the successive 

 geological formations, and concludes by stating that " from the 

 earliest time down to the present day, the physical and chemical 

 conditions under which phosphatic deposits have been formed 

 have remained essentially the same." A useful bibliography of 

 the subject is appended. 



' In the Bulletin de la Classe des Sciences of the Brussels 

 Academy {1900, No. 4), M. Louis Dollo, curator of the Brussels 

 Museum, describes the new fish, Racovitzci glacialis, discovered 

 in the Belgian Antarctic Expedition. This is the third new 

 fish discovered by the party, and only one specimen was found, 

 and that a small one, somewhat mutilated at the caudal ex- 

 tremity, the length of the body, exclusive of the tail, being 

 82 millimetres. It was found on May 28, 1898, in lat. 71° 23' S., 

 long. 87° 32' W., depth 435 metres, and is a member of the 

 family Trachinidae, distinguished from the genera Bathydraco, 

 Bembrops, Chfenichthys, Cryodraco and Gerlachea by well- 

 marked characteristics, which M. Dollo describes. It is, how- 

 ever, most nearly allied to Bathydraco and Gerlachea, and its 

 existence within the Antarctic Circle furnishes a fresh proof of 

 the frequency of the Trachinidre in the neighbourhood of th is 

 circle. 



