158 



NATURE 



\_June 15, 1882 



current to flow. A " rheostat-chain," the invention of M. 

 Reynier, who in 1881 applied a similar device to a sewing 

 machine driven by electricity at the Paris Exposition, is 

 thereby stretched. As its tension increases, there is 

 better contact electrically between its links, and with this 

 better contact the electric resistance diminishes ; the 

 flow of current and consequently the speed of the engine, 

 is therefore increased. By moving the lever in one 

 direction or the other, the speed of the train may therefore 

 be varied at will. When the lever is put back to its posi- 

 tion of rest, it not only breaks contact, but also puts on 

 the brake. To reverse the motion of the train, there is a 

 second lever, which shifts the brushes of the dynamo. A 

 third lever sets the wheels of the dynamo in gearing 

 either with the axle of the locomotive, or with the hauling 

 machinery previously mentioned. 



The tender (Fig. 2) attached to the locomotive holds 

 the accumulators, which are of the type constructed by 

 M. Reynier, consisting of two lead plates covered with 

 red lead, and wrapped in felt or serge, rolled together in 

 a spiral, placed in dilute acid in a stoneware jar. These 

 cells are arranged (Fig. 2) in three tiers in baskets, each 

 basket holding six cells. On each shelf are four baskets, 

 except on the uppermost, which holds two only. The 

 sixty accumulators weigh 500 kilogrammes (half a ton). 



c 



Fig. 5. — The starting-gear, with chain rheostat. 



The total weight of the locomotive is less than a ton, 

 that of the tender 700 kilos. (1543 lbs.), and that of each 

 loaded truck 800 kilos. (1763 lbs.). With the workmen 

 and six passengers, the total weight of the train is 6400 

 kilogrammes (about 6i tons). The accumulator cells are 

 charged at the factory by the current of a Gramme 

 machine, which has been used since 1879 to light the 

 establishment by eleven Reynier lamps. The power 

 available in the works is 60-horse. (inly 3 horse-power 

 is, however, required during the charging of the cells, 

 which takes from five to eight hours. 



In the top of the tender is a switch, by means of which 

 the accumulators can be used in rotation, beginning with 

 a minimum of twenty-four, and increasing successively 

 by sixes up to sixty cells. 



This railway has worked since March last with results 

 advantageous in every way. The speed of the train 

 attains 12 kilometres (about 74 miles) per hour; but in 

 this special case, great speed is not desired. According 

 to the information furnished by M. Dupuy, the train can 

 work for three hours ; being limited only by the charge 

 that can be imparted to the accumulators' 



This application of electricity to a purpose for which a 

 steam-engine would be out of the question, is not only 



novel, but suggestive. We feel disposed to query how 

 long it will be before that great section of the public of 

 London who travel by the Metropolitan Railway, insist 

 that their lungs and eyes have as much claim as the linen 

 of M. Duchesne-Fournet to be protected from the dis- 

 astrous presence of the smuts and scoriae of the steam- 

 engine. 



THE WEATHER OF THE PAST WEEK 



THE very disagreeable weather we have had these last 

 few days deserves a passing notice. Strong per- 

 sistent northerly winds for nearly a week have swept over 

 the whole of the British islands. On Sunday and Mon- 

 day a continuous north-easterly gale blew over Shetland 

 and Orkney, completely interrupting all communication 

 among these islands, accompanied with heavy rains, 

 floods, and hailstorms ; and at the same time much snow 

 fell in the upland districts of the interior of North Britain, 

 draping the mountains of Aberdeenshire and Perthshire 

 in their winter covering of snow down nearly to their 

 bases. On the other hand, in England and Scotland, 

 much thunder and hail occurred towards the end of last 

 week, and not a few lives were lost by the severity of the 

 thunderstorms. These disagreeable and remarkable phe- 

 nomena were attendants on an atmospheric depression 

 signalled by the Meteorological Office on Thursday 

 morning, last week, as about to advance over the more 

 southern parts of these islands. The depression appeared 

 in course, its centre following the line of the Cheviots ; 

 and its northern side being characterised by unwonted 

 high pressures, it proceeded with singular leisureliness over 

 the North Sea, and only reached Christiania by the morn- 

 ing of Monday. The slow onward rate of motion of this 

 cyclone, the steep gradients formed on its north and 

 north-west sides, and its southerly route across the 

 North Sea readily explain the extent, strength, persis- 

 tence, and disagreeably low temperature of the gale, and 

 the unseasonable snowfalls which accompan ed it. It is 

 to such low depression-centres brooding over or slowly 

 crossing the North Sea, that we owe our coldest summer 

 weather ; and it is a continued repetition of these in the 

 critical months of June, July, and August that brings 

 disaster to the farming interests. In the middle of June, 

 1869, a similar storm occurred when equally strong winds 

 prevailed, when even more snow fell, particularly in the 

 north-west of Great Britain, and temperature sank some 

 degrees below freezing over extensive districts ; but the 

 storm was of shorter duration than the one we have just 

 had. In this case, also, the cyclone formed steep gra- 

 dients for northerly winds, and its centre crossed England 

 and the North Sea, but it advanced over North- Western 

 Europe at a more rapid rate than the present storm, 

 which has formed so marked a feature of the weather of 

 June, 1882. 



NOTES 



We take the following from the Times: — At the meeting of 

 the Royal Society last week, the fifteen undernamed candidates 

 were elected Fellows: — Prof. Valentine Ball, M. A., George 

 Stewardson Brady, M.D., F.L.S., George Buchanan, M.D., 

 Charles Boron Clarke, M.A., F.L.S., Francis Darwin, M.A., 

 F.L.S., Prof. William Dittmar, F.C.S., Walter Holbrook Gas- 

 kell, M.D., Richard Tetley Glazebrook, M.A., Frederic Ducane 

 Godman, F.L.S., Prof. Jonathan Hutchinson, F.R.C.S., Prof. 

 Archibald Liversidge, F.G.S., Prof. John C. Malet, M.A., 

 William Davidson Niven, M.A., Robert Henry Inglisi Palgrave, 

 F.S.S., Walter Weldon, F.C.S. 



It is interesting to notice, that in connection with the vote of 

 sympathy of the Common Council on the death of Garibaldi, 

 the Lord Mayor stattd that "on the death of the great philo- 



