February 22, 1894] 



NATURE 



395 



as the velocity, while, if the results obtained with one of the 

 resonators which M. Blondlot thinks are less trustworthy are 

 omitted, the mean becomes 302,850 kilometres per second, the 

 maximum variation obtained from this mean amounting to 2'5 

 per cent. The author also points out that it is interesting to 

 note that the mean value of the velocity of propagation of 

 electro-magnetic waves obtained is about one per cent, higher 

 than the velocity of light. The difference he considers to be 

 due to the fact that the calculated value of the self-induction is 

 too small, for the radius of the wire is an important factor, 

 which may be estimated too large, either owing to errors in 

 measurement or to the fact that the current in the wire is not 

 exclusively confined to the external surface of the wire (as the 

 formula employed supposes), but penetrates some distance into 

 the wire. The employment of wires of larger section, he thinks, 

 might perhaps lead to a better result. 



With reference to some recent experiments on the railway 

 between Beuzeville and Havre, \.\\^ Electrician says : — " When, 

 about three years ago, a scheme was announced for building a 

 locomotive on which a high-speed engine was to drive a three- 

 phase alternator, which was in turn to drive motors, it met with 

 a little ridicule, and the two sets of tests which have been re- 

 ■cently made on the Chemin de Fer I'Ouest at Havre have raised 

 a smile, but only where the reasons of this roundabout system 

 have not been understood. The two chief difficulties in obtain- 

 ing higher speeds than from 70 to 80 miles an hour with ordinary 

 express locomotives are want of balance and want of space. The 

 impossibility of avoiding the superfluous vertical action of bal- 

 ance weights on an ordinary single-wheel locomotive is alone 

 sufficient to reduce adhesion, and to allow slip at speeds a liitle 

 over 80 miles an hour. All these difficulties are reduced, if not 

 avoided, in the Heilmann locomotive, thout;h not without the 

 introduction of others, and it remains to be seen how the balance 

 of advantage works out." 



Mr. H. Work Dodd has investigated the question as to a 

 relationship between epdepsy and errors of refraction in the eye, 

 and the current number of Brain (pirt Ixiv.) comainshis results. 

 He has examined the eyes of one hundred case^ of true epilepsy, 

 and compaied the refractions with those of apparently normal 

 eyes. It appears that of simple hypermetropia there were 

 twenty-eight cases per cent, less in the epileptic than in the 

 apparently normal class. Of astigmation of all kinds, there 

 were twenty-six cases per cent, more in the epileptic division 

 than in the normal one. These and other differences lead Mr. 

 Dodd to conclude that, given a certain condition of instability 

 of the nervous system: (i) errors of refraction may excite 

 epilepsy ; (2) the correction of the errors of refraction will, in 

 combination with other treatment, in many cases cure or relieve 

 the epileptic condition ; and (3) that in some cases, when the 

 refraction error has been corrected, the epilepsy will continue, 

 generally in a modified form, in consequence of other irritation, 

 €ven though the error of refraction may have been the exciting 

 cause of the fits in the first instance. Mr. Dodd is strongly of 

 opinion that in every case of epilepsy — in addition to general 

 treatment and llie investigation of other organs — the eyes should 

 be carefully examined under a mydriatic with a view of correct- 

 ing any error of refraction that may exist by the use of proper 

 spectacles. 



The bacterial contents of ice from various sources has been 

 very exhaustively investigated, but only a few experiments have 

 been made on the vitality of particular micro-organisms in 

 artificially frozen ice produced by means of freezing mixtures 

 Prudden exposed various bacteria to 24° of cold, and amongst 

 these the typhoid bacillus was found still present in large 

 numbers after 103 days of continaous exposure to this low 

 temperature ; if, however, the freezing was interrupted during 

 iNO. 1269, VOL. 49] 



the twenty-four hours by three separate thawings, they were 

 entirely destroyed at the end of three days. Prudden also 

 showed very clearly that the resistance of an organism depends 

 upon its initial vitality, for whereas the staphylococcus pyogenes 

 aureus taken from a fresh agar cultivation was present in very 

 large numbers at the end of sixty-six days, if an old and half 

 dried-up agar culture was used for the original infection, 

 none were found after seven days. Renk (Fortschritte der Med. 

 No 10, 1893) has quite recently examined the behaviour 

 of the cholera organism in ice artificially prepared from 

 sterilised river Saale water, and finds that five days unin- 

 terrupted exposure to a temperature of from — 0*5 to — 7° C. 

 is sufficient to entirely destroy these bacilli ; but contrary to 

 Prudden's experience, he found that if the freezing was 

 interrupted, which took place when the vessels containing the 

 organisms were removed for examination, a longer time (6-7 

 clays) was necessary for their annihilation. When unsterilised 

 Saale water was used, the cholera organisms disappeared at the 

 end of three days, and the ordinary water bacteria present 

 were reduced in 24 hours from 1,483,000510 62,445 per c.c. 

 whilst after three days only 4480 were found. Prudden's 

 experiments with the typhoid bacillus, together with those on 

 the cholera organism, indicate how important it is that ice for 

 consumption should only be prepared from sterilised water, 

 or from water the source of which is altogether beyond 

 suspicion of contamination. 



The Societe d'Encouragement pour I'lndustrie Nationale has 

 issued its Annuaire for 1894. 



With the present year the bi-monthly cryptogamic journal, 

 Heiwi^ia, published at Dresden, and edited by Prof. G. 

 Hieronymus, commences the publication of a periodical synopsis 

 of cryptogamic literature. 



We have received a copy of "Bourne's Handy Assurance 

 Directory" for 1894, The work appears for the first time under 

 the imprimatur of Mr. William Schooling, who will doubtless 

 sustain the reputation for accuracy earned for it by the late 

 editor, Mr. William Bourne. 



Dr. M. Baratta has prepared a series of maps showing the 

 topographical distribution of earthquakes in Italy for each year 

 from 1887 to 1891. The maps, which originally appeared in 

 the Annali deW Ufficio Centrale di Meteorologia e Geodinamica, 

 should be of great interest to seismologists. 



The second volume of Sir David Salomons' " Electric Light 

 Installations," dealing with apparatus, engines, motors, 

 governors, switches, meters, &c. will be shortly issued in Messrs. 

 VVhittakers' "Specialists' Series." The third and concluding 

 volume is now in the press, and will deal with the application 

 of electricity. 



Mr. W. Thynne Lynn's "Celestial Motions" (Edward 

 Stanford) has reached the eighth edition. The first edition of 

 this useful little book was published ten years agn. Another 

 little treatise by the same author, " Remarkable Comets," has 

 just passed into a second edition. Both books have been 

 revised and brought up to date. 



An important report on the Ainu of Yezo, Japan, prepared 

 for the U.S. National Museum, by Mr. Romyn Hitchcock, has 

 been received. It is profusely illustrated from photographs 

 taken by the author, and contains a mass of detail concerning 

 the remnant of a once numerous people in Yezo and on the 

 islands Kumashiri and Zeterof. 



Messrs. Bliss, Sands, and Foster announce that they 

 have made arrangements with the editor of " A Son of the 

 Marshes," and with Prof. Boulger, for the joint production of 



