February i, 1900] 



NA TURE 



3-^9 



with those made at Barnaul and Irkutsk, as also with the normal 

 isobars, General Tillo comes to the conclusion that the prolable 

 iltilude of Lukchun must be 17 metres below the sea- level, with 

 a probable error of + 15 metres. The spot where the baro- 

 nuter was ob<<erved is not, however, the lowest part of the 

 lepression, as its altitudes are in different places from 36 to no 

 metres beloiv \\\?a. place— ihu-s giving negative altitudes as deep 

 IS 130 metres + 15 metres below the sea-level at Tash-tura. A 

 )od map of the depression is given with the paper. Besides, 

 le meteorological observations made at Lukchun are most 

 interesting in themselves, as it appears from them that the yearly 

 amplitudes of the birometer are greater at this place than any- 

 vhere on the earth — the monthly averages for January being by 

 full 30 mm. in excess of those for July, while the daily ampli- 

 tudes in the winter are as great as in some tropical lands. The 

 iiighest temperature observed in July (48" C ) is also one of the 

 highest observed in Continental Asia, and is truly Saharian. So 

 is also the dryness of the air. 



A PAPER, on a " New Basis for the Foundation of Geometry," 



has been issued, bearing the signature " E. G. L," but whose 



author invites criticisms addressed to Mr. F. VVheatcombe, of 



Manchester. The writer of the paper is by no means alone in 



lis ideas as to Euclid's treatment of parallel lines, his definition 



if a plane angle to the exclusion of straight angles and other 



-uch matters being unsatisfactory. As he contemplates writing 



I book on the subject, we only hope that he will first have 



studied the considerable mass of existing literature upon it ; and 



if the work is to be properly treated the author should be 



versed in non-Euclidian as well as Euclidian geometry. The 



•rsistent survival of Euclid's "Elements" as a text-book on 



imetry is mainly due to his sequence of propositions, stereo- 



ped and standardised by constant usage, affording teachers a 



iinnon starting point. Many have tried to improve on Euclid ; 



t as long as scarcely two people think alike as to how this is 



he done, so long will their proposals fail to take root. 



The January number of the Philosophical Magazine contains 

 paper, by Dr. C. Davison, on earthquake sounds, a somewhat 

 _;lecied branch of seismology. The sound is described as 

 iierally deep and rumbling, like that of a heavy waggon 

 -sing ; sometimes it resembles thunder or wind more closely, 

 c fall of heavy stones, or the firing of distant cannon. Near 

 epicentre of the earthquake, loud crashes are heard by some, 

 It not all, observers at the time when the shock is strongest ; 

 further away, it becomes rougher and more grinding at this 

 moment ; while at a great distance, the sound is throughout 

 smooth and almost monotonous like the low roll of distant 

 thunder. The neighbourhood of the sound to the lower limit 

 f audibility is shown by the fact that it is heard by some 

 servers, as say, like the rumbling of a heavy traction-engine 

 losing, while others equally alert hear no sound at all. To 

 ■ iitferent auditors of the sound, it also varies in character and 

 iluration for the same reason. In this country, practically 

 every earthquake is accompanied by sound, which both precedes 

 and follows the shock ; in Japan, the sound is frequently 

 absent even from violent earthquakes, it is seldom heard more 

 than a few miles from the origin, and rarely, if ever, follows the 

 shock. It would therefore appear that the Japanese as a race 

 are inferior to us in their powers of perceiving deep sounds. 

 In strong earthquakes, the sound-area occupies a region sur- 

 rounding the epicentre; in weak ones, the sound-area and 

 lisuirbed area approximately coincide, or the former area 

 ■)verlaps the latter ; while in certain districts the sound is 

 sometimes heard without any shock being felt. Several instances 

 of these earth-sounds are given, and it is urged that they are 

 merely earthquakes too weak to be felt. Dr. Davison believes 

 that earthquakes are caused by fault-slips, and that the sound- 

 NO. 1579, VOL. 61] 



vibrations come chiefly from the margins of the area of displace- 

 ment. He shows that this theory will account for all the 

 known phenomena of earthquake-sounds. 



In the Prorcedings o{\.\\e Liverpool Geological Society (I'ait 

 3, vol. viii., 1899) we have an address from the ex-President, 

 Mr. J. Lomas, in which he deals with the characteristic litho- 

 logical characters of the principal geological systems. In 

 another article he describes and figures "some flint implements 

 found in the glacial deposits of Cheshire and North Wales." 

 Concerning the artificial form of some of these, Mr. VV. J. 

 Lewis-Abbott speaks with confidence, whereas Sir John Evans 

 remarks " No. 7 may be artificial. Of the others, Nos. 2 and 

 3 look the most possible ; but the signs are not such as can 

 confidently be relied on. If man existed in pre-glacial times 

 in Britain, it is, I think, probable that his tools would have 

 been of larger proportions." Mr. Mellard Reade describes a 

 great boulder of gypsum which was found at Great Crosby ; he 

 also enumerates the Foraminifera found in samples of Cheshire 

 boulder-clay. Mr. G. H. Morton describes his geological map 

 of Liverpool, and Mr. T. H. Cope deals with the gabbro of 

 Llyn Eigiau, above the valley of the Conwy. 



"Y^w. Journal de Physique for January reprints an article on 

 the Phase rule of Prof. Willard Gibbs, taken from the intro- 

 duction of the work by Mr. Wilder D. Bancroft. In this 

 article, the rule in question is very simply explained. 



The Bulletin of the Cracow Academy (November) contains 

 a continuation of M. P. Rudski's researches on the elastic de- 

 formations of the earth. It deals with the deformations pro- 

 duced by glacial deposits or by the formation of coral reefs. 



O.N account of the comparatively dull light of the English 

 climate, the lenses usually possessed by Kodaks and other hand- 

 cameras have too small an aperture to be used for many pur- 

 poses. Messrs. Taylor, Taylor and Hobson have, therefore, at 

 the request of many photographers, made arrangements for re- 

 fitting such cameras with their well-known Cooke lenses. As 

 the lenses can be attached to almost any hand-camera now upon 

 the market, their rapidity will soon ht widely known. 



As in previous years, the "Annuaire" of the Brussels Ob- 

 servatory contains particulars of the principal astronomical oc- 

 currences for the current year, geographical information, tables 

 of physical and chemical data, and other statistics of frequent 

 service in scientific work. The articles include a discussion of 

 the meteorological observations of 1899, and of the direction of 

 the wind at Brussels, by M I^ankaster ; on the use of the kite 

 in meteorology, with a bibliography of the subject, by M. 

 Vincent ; the climate of the Belgian coast, by M. Durieux ; the 

 population of Europe, by M. Lankaster ; reports on various 

 branches of astronomical and meteorological work carried on 

 last year, and an instructive description of the determination of 

 the co-ordinates of sun spots, by M. Niesten. 



Many workers with the microscope have been guided in their 

 early "dabblings" by the late Rev. J. G. Wood's "Common 

 Objects of the Microscope ' (Roulledge and Sons), and not a 

 few can doubtless recall their failures in the attempt to mount 

 seeds in Canada balsam and their disappointment that the 

 medium refused to set in six to eight hours. A new edition of 

 this deservedly popular book has now appeared, revised and 

 brought up to date by Mr. E. C. Bousfield. The late Mr. 

 Tuffen West's familiar illustrations appear to have been re- 

 engraved, and fly leaves with lists of the figures are now attached 

 to the plates, while Mr. Bousfield has added two plates of his 

 own drawing illustrative of pond life. The new letterpress 

 includes a brief account of the optics of magnification, and the 

 use of the substage condenser (brought into general use since the 

 first edition of " Wood ") in the introductory chapters, and 



