346 



NA TURE 



\_Aiigust 12, 1880 



extent of the ground is 300,000 square metres, and the area 

 covered by the palace 70,000. The number of exhibitors is 

 7,000, or more than one for each 1,000 inhabitants in a popnla- 

 tion of about 6,000,000. Two of the pavilions are occupied by 

 the two principal telephonic companies, who are competing at 

 Brussels, Antwerp, and Verviers, where rival central offices have 

 been built, and are besieged by a crowd of experimenters. The 

 number of tickets sold at the gate is about 10,000 a day, which 

 is considered a success. It was attempted to establish a 

 captive balloon on the model of the large GifTard captive balloon 

 on a reduced scale, the ro|3e being only 300 metres long instead 

 of [500, and the volume 8,/ioo cubic metres instead of 25,000. 

 But in spite of this diminution the balloon refused to go up, the 

 hydrogen having been mixed with a large quantity of common 

 air. The Belgian balloon has been disinflated, and fresh efforts 

 will be made to till it with better gas, but success is con- 

 sidered rather doubtful. Except this disappointment, which it 

 shares with ^Berlin, Vienna, and New York, where attempts 

 to start a captive balloon failed, everything is going on remark- 

 ably well at Brussels. It is difficult to give a brief description of 

 all the objects worthy of notice in this wonderful display of 

 Belgian enterprise and skill. In the engine hall a facsimile of 

 the first locomotive constructed on the continent has been placeJ. 

 It bears the date of 1S35, and an inscription shows it was male 

 by Cockerill for the Belgian Government Railway. One of tlie 

 wonders of the Exhibition is the collection of models of 

 mining, showing all the incidents of underground workings and 

 living. Scientific societies and Government exhibit complete 

 collections of the mineral and vegetable kingdoms within the 

 limits of Belgian territory. Every provincial Government is 

 an exhibitor, and also the various Central Government Depart- 

 ments. The Belgian Photographic .Society has organised a very 

 good display. The Brussels Observatory has sent a model of 

 van Rysselberghe's self-registering meteorograph. This appa- 

 ratus is in operation at the Brussels Observatory, in Antwerp, at 

 Ostend, and at Arlon. When the Belgian Observatory is moved 

 to a new situation at some distance from the city, all these instru. 

 ments will be connected with it by a special telegraph wire, S3 

 that the physicists of the Meterological Office will write their 

 predictions in a room where they will be able to watch 

 the development of meteorological phenomena all over their 

 native country. An electrical railway has been established in 

 the gardens, and is working all day long with perfect regularity. 

 The number of waggons is three, each of them carrying six 

 passengers, with a velocity of 3 metres per second, to a distance 

 of 300 metres, for 31/. The locomotive, of which the « eight is 

 800 kilogs., carries a Gramme machine, worked by another 

 machine, which is stationary. There is also in another part of 

 the city a so-called International Exhibition, but this, although 

 opened in state by the King, is merely a private speculation, 

 without having any special feature or deserving any particular 

 notice. 



Sir William ITarcourt stated in the House of Commons 

 the other day that it is hoped that the work of the Cambridge 

 University Commissioners will be completed before the Christmas 

 Vacation. 



Prof. Mendeleef is at present in the Caucasus. He intends 

 to visit Vladikavkaz, Tiflis, Batoum, and Poti, whence he 

 proposes to proceed to Kertch to inspect the sources of 

 petroleum. 



The ladies continue to keep well to the front in the University 

 of London Examinations. In tlie first division of the first B.Sc. 

 examination the fourth on the list is Miss Sophia Bryant. The 

 other five ladies are well up in this division, there being none so 

 low as the second. In the first division of the first B.A. 

 Examination the second on the list is Miss Catherine Eyre 

 Anelay. 



Great activity prevails at the Meudon aeronautical school, 

 where the French Government has established extensive works 

 for the construction of a large number of war balloons. Each 

 of these, 10 metres in diameter, will be made of silk, varnished 

 by a process invented in 1794. The valve is to be made of 

 metal, and the shape will be quite spherical. Not less than 

 forty of them will be sent to the several French armies for the 

 purpose of making captive or free ascents when required. Of 

 these more than half have been already constructed. The con- 

 struction of furnaces for the preparation of pure hydrogen has 

 not begun yet. The warehouse is large enough to contain 

 inflated balloons, which can find exit by the roof. All the men 

 and officers (except one) belong to the corps of Military Engineers. 

 All the works for building du-ecting balloons have been stopped. 



The Daily Neias Naples correspondent writes that Prof. 

 Silvestri wrote from Catania on July 15 that since his report on 

 May I last about the eruption of ashes from Mount Etna he has 

 observed many other interesting phenomena. On May 16 and 

 17 last some slight shocks of earthquake were felt on the east 

 side of Mount Etna, especially in the district of Acireale. 

 About a month later the shocks commenced again and were 

 repeated on sever.il consecutive days — that is on June 15, 16, 17, 

 and iS. The motion was undulating. About two days before 

 these manifestations a new and very active phase of mud erup- 

 tions set in at Paterno, on the south-east of Etna. Two craters 

 opened, which violently ejected gaseous matter with abundant 

 torrents of mud, more consistent than usual, and of a higher tem- 

 perature (140 degrees Fahrenheit), which, accumulating in the 

 basins in large masses, finally broke through all barriers, over- 

 flowed and destroyed the adjoining fields, and buried several 

 mills and farmhouses. In this eruption Prof. Silvestri noticed 

 an abundant development and pressure of gaseous matter, of 

 such force that it produced oscillations strong enough to tear up 

 the old lava, forming rents out of which the gas rushed with the 

 noise of a boiler letting off its steam. Coincident with these 

 phenomena clouds of vapour issued from the eruptive fissure of 

 last year, confirming the opinion formed by the Professor before 

 — namely, that this fissure, lying between the two principal 

 craters of 1879 and the great central one, had not been blocked 

 with lava, but was still in communication with the centi'al 

 eruptive axis, for vapour, mixed with ashes which fell all over 

 the cone, also issued from the central crater. This activity 

 continued during several days, and still continues with decreased 

 intensity, seen from Catania in the shape of dense clouds cover- 

 ing the whole summit of Etna in a clear sky. Changes have 

 taken place which have entirely altered the form of the central 

 crater. The old ravine, which formerly crossed the crater and 

 made two-thirds of it into an ample and easily accessible basin, 

 a natural laboratory for the study of the products of the volcano, 

 now exists no longer. The central crater, from the effects of 

 violent commotions, has crumbled, and, with part of its sides 

 and the high point whence it was formerly possible to enjoy the 

 sunrise, has been precipitated into the ravine, diminishing the 

 height of the mountain by about 40 feet, w hile the circumference 

 of the crater has become wider by half a kilometre. The 

 general destruction of the old sides has in a certain way 

 rejuvenised the crater, wliich has regained its characteristic 

 form of a funnel, at the bottom of which is now the eruptive 

 mouth. 



A letter from San Jose_ de Guatemala, dated July 2, to the 

 Panama Star and Herald, says:— "At 3 a.m. on June 29 the 

 volcano Fuego suddenly became active, throwing out vast 

 showers of fire and cinders, with great darts of flame shooting 

 up from 350 feet to 500 feet above the mouth of the crater. The 

 whole country to the east and south was magnificently illumi- 

 nated. At 3.40 a.m. two streams of lava could be seen running 

 down the sides of the volcano, one to the south and east, the 



