NATURE 



[Feb. 5, i! 



Lakes Geneva, Neuchatel, Morat, and Bienne, and the neigh- 

 bouring valleys. The quite level surface of this fog is likened to 

 that of a sea of milk which reached as high as 500 feet beneath 

 the 4,900 feet high Col de Jaman. At Rossinieres the planet 

 Venus was seen with the naked eye in daylight from October 23 

 until the end of December. 



Another interesting note, by Prof. Plantamour, inserted in the 

 same number of the Archives, deals with the temperature of the 

 St. Bernard. It happens every year that the temperature on 

 the St. Bernard, during several hours, or even during several 

 days, of December, is higher than at Geneva. But during 

 December, 1879, this anomaly lasted for a far longer period of 

 time than usual ; the average temperature of December on the St. 

 Bernard (2,070 metres above Geneva) was 8°'4 Celsius higher than 

 at Geneva ; out of the thirty-one days of the month only during 

 fourteen days was it from o 'O4 to 6°"2 Celsius lower than at 

 Geneva, whilst during seventeen days it exceeded this by 2° to 

 l6°'4 (l6° - 4 on December I, 13° on December 5, 7, and 31 ; 11° 

 on the 8th, 13th, and 30th, and so on). Prcf. Plantamour ob- 

 serves also how difficult it is in such cases to determine the mean 

 temperature of the stratum of air between the two stations, and 

 how great the error of the barometrical levelling and of the 

 reduction of the observed pressure to the sea-level would be if 

 we applied the barometrical formula to such cases when the 

 usual distribution of heat is inverted as it was during December 

 last. As to the temperature at Geneva, it was, during this 

 month, 6° '9 Celsius lower than the average for fifty years ; this 

 difference exceeded four times the probable difference which, 

 when deduced from fifty years' observations, is only ± I°'72, 

 the probability of such a difference being only o'oo5- 



The results of a recent instructive experiment in sylviculture, 

 extending over seventeen years, have been communicated to the 

 French Academy by M. Gumaud. His conclusions are as 

 follows : — (1) That light when it strikes the ground, after being 

 sifted in the foliage, stimulates the production of carbonic acid 

 in the decompositions which produce humus, and also the decom- 

 position of that gas by the green parts. (2) That the growth of 

 tall trees is retarded, though their green parts expand freely in 

 the atmosphere, under direct impression of the luminous rays, 

 when the lower covert formed by trees of smaller size intercepts 

 too completely the access of light to the ground, and diminishes 

 its reflex action on the tops of the tall trees. (3) That the 

 covert formed by underwood weakens this reflex action of light 

 on the vegetation of tall trees rather by its composition, than in 

 any other way ; since, after a clearing which suppresses the 

 oblique shoots, the vertical shoots retained do not offer any 

 obstacle. (4) That humus, under too dense a covert, loses a 

 part of its efficacy, and herein resembles farm-dung, which, too 

 deeply buried, remains inert for several years. En risuml, it is 

 demonstrated how the vegetation of tall trees may be improved 

 by operating on the composition, consistence, and duration of 

 the underwood. 



A correspondent of the Times writing from the Royal Mail 

 Steamer Para aX sea, January 17, records a volcanic eruption 

 in the Island of Dominica, and also disastrous floods in St. 

 Kitts. On Sunday, January 4, at II. 5 a.m., the inhabitants 

 of Roseau, the capital of Dominica, a town situate on its 

 western shores, were suddenly plunged into almost total dark- 

 ness, for, although it had been raining heavily all the morning, 

 the sky up to half-past ten was fairly clear, and there was no 

 warning of what was to come except a strong smell of sulphur 

 pervading the atmosphere, and this, in an island abounding in 

 sulphur springs, is so usual that few of the inhabitants had even 

 noticed it. With the strange darkness came torrents of milk- 

 white water, mixed with black volcanic sand and ash, flashes of 

 bright red lightning, peal after peal of thunder, while ever and 

 aaon between the peals could be heard a strange subterranean 



noise like the breaking of waves on a lee-shore. This lasted 

 nearly fifteen minutes. When daylight was restored the town 

 was found to be covered with ashes an inch deep, and the sur- 

 rounding country presented a most abnormal appearance. The 

 cause of this strange volcanic phenomenon did not long remain 

 a mystery, for next morning, during a lull in the deluge of rain, 

 there could be seen hanging over the " Boiling Lake " crater, 

 and in clear outline against the sky, a cloud such as the younger 

 Pliny describes as having hung over Vesuvius in Augast, 79, of 

 our era. The now famous "Boiling Lake" of Dominica is the 

 centre of a large crater in the southern extremity of the island, 

 called the Grand Souffriere HilK During the eruption nearly 

 all the rivers in the island overflowed their banks, and in the 

 Point Mulatre River, which rises from the crater of the " Boiling 

 Lake," all the fish, even those near to the estuary, died, and 

 were subsequently taken out in basketfuls by the natives. The 

 flood in St. Kitts occurred on Sunday, January II. The storm 

 began about IOP.m with heavy rain, which" gradually increased 

 in intensity until midnight, when it almost seemed to be rain, 

 and seemed to assume the character of a falling waterspout. 

 During this time there were occasionally strong blasts of wind, 

 very vivid lightning, and once or twice a tremulous undulating 

 movement of the earth. There was, however, only one severe 

 shock, and it is said to have occurred about 2.30 a.m. on the 

 1 2th, when the full fury of the storm was attained. After this 

 it began to decrease in violence, and at 4. 30 all was silent, and 

 the work of destruction was over. 



An international exhibition of plants and flowers will be held 

 at Weisbaden during the approaching summer. 



At Geneva an international exhibition of clocks and watches, 

 and of all machines, implements, utensils relating to clock 

 making, will be held during May and June next. 



Ice-blocks have been formed not only at Saumur but also at 

 Lyons. These occurrences are not unexampled, as it appears 

 that in the terrible winter of 1840 the Vistula was also blocked 

 by ice, close to Dantzig ; the result was that the stream opened 

 a new bed in a sandy and hilly ground. The channel for pre- 

 venting the level of water rising higher than the top of the 

 embankments has been bored by explosions in the Saumur ice- 

 berg. The work was begun on the 16th and was ended on the 

 22nd. The section is from 10 to 20 metres. Since that time 

 the engineers have been busy enlarging it, and the work is pro- 

 gressing favourably. The iceberg has been measured carefully, 

 and estimated at 15,000,000 cubic metres. The navigation arm, 

 on the right side, has been hopelessly blocked, and no work has 

 been tried. The weather is splendid, the sun extremely hot 

 during day, but the nights are very cold. On Tuesday morning 

 all the streets were covered with ice. 



It has been noted that during the present weather crisis the 

 Montsouris electrometers have shown not a single negative reading. 

 This positive state has continued for the last three months- 

 The readings are taken eight times a day. 



The recently opened Albert Institute at Windsor made a 

 good beginning on January 20 with an interesting lecture by Mr. 

 F. Drew, of Eton, on "The Objects aimed at by the Institute.'' 

 Mr. Drew showed the great interest attaching to the study of the 

 various branches of science, giving some useful practical hints as 

 to how the study both of science and of literature may be most 

 effectnally carried out. 



We notice a useful Russian work by M. Tchikoleff, on "The 

 Electric Light and its Applications to Military Purposes," being 

 a thorough description, with numerous figures of the various 

 apparatus employed in the armies of various countries. 



Mr. Gordon Holmes's work on "Vo=al Physiology" is not 

 published at Edinburgh, but by Messrs. Churchill, of London. 



