322 



NATURE 



{Aug. 10, 1876 



Natural History, during 1875, with electric thermometers 

 placed in the air, and in soils covered with grass and soils 

 cleared of vegetation. From the results of the last four years, 

 it is shown that the mean annual temperature of the two soils, at 

 a depth of 39 inches, and that of the air, is nearly alike ; that 

 at depths of from 4 to 24 inches the influence of vegetation is to 

 raise the annual mean o°7 above that of soils clear of vegeta- 

 tion ; and that during these four years the temperature of soils 

 covered with grass or any other vegetation has not fallen to 

 freezing (32°), a fact of no little importance to horticulture. 



Experiments were made at Paris recently, before M. 

 Baron, Director of the Electric Telegraph, on a new system 

 for dividing the electric light. A single generator has fed with an 

 admirable regularity not less than eighteen lamps, having each a 

 power equal to 100 gas-jets. The effect was wonderful, and 

 the apparatus will be tried shortly at the Lyons railway terminus. 

 The principle is very simple, and was discovered by a working 

 shoemaker. The current derived from a Gramme machine, 

 slightly modified, is sent to a second machine, which rotates 

 before forty-eight electro-magnets, four of these electro-magnets 

 having a force sufficient to give a light equivalent to lOO gas-jets. 

 Twelve electric lamps can be fed at any distance. By a very 

 simple commutator any number of these twelve lamps can be 

 grouped together, so that one, two, or more can be set in the 

 same apparatus. Twelve working on the same point give a real 

 burning sun. The force required for working both machines (the 

 prime mover and the distributor) is derived from a 4 horse-power 

 steam-engine. The experiments at the Lyons railway will be 

 tried with sixteen lamps and an engine of from 6 to 7 horse- 

 power. The light will be equal to 1,600 gas-jets. 



The French Society of Agriculture and Insectology will, as 

 usual, hold its bi-annual exhibition at the Orangerie des Tuileries 

 in September. The exhibition being universal, some contributions 

 are expected from England, The last having been a success, 

 left a large surplus in the hands of the Society, which will 

 enlarge the scale of its operations. 



Some details regarding the malacological fauna of the Island 

 of Saint Paul have been furnished by M. Velain, in a note to the 

 French Academy, and will doubtless interest zoologists. Little 

 was previously known of this fauna. The island, it is known, 

 is more than 500 leagues distant from any continents, and the 

 tranquil lake in the old crater of the volcano seemed likely to 

 favour the development of embryos brought by oceanic currents. 

 The list of Gasteropoda and Lamellibranchia comprises forty 

 species, distributed in twenty-nine genera, five of which are new. 

 This fauna, notwithstanding the small latitude of the island, is 

 remarkable for its austral forms. The species are mostly of 

 small size, rarely exceeding 3 mm. ; among them appear as a 

 giant the Ranella described by Frauenfeld, which sometimes 

 reaches 8 cm. in height. The island maybe said to have two dis- 

 tinct fauna, that of the interior of the crater and that of the exte- 

 rior ; the latter is less rich ; the abrupt sides, environed with reefs 

 on which the sea incessantly breaks with violence, being hardly 

 favourable to the thriving of marine molluscs. The species here 

 have short, rounded forms, with thick shells. Within the crater 

 the littoral zone is extraordinarily rich in individuals, though not 

 in species. The conditions are : a rocky bottom exposed to the 

 light, weak pressure, temperature kept nearly constant by 

 thermal springs (13" to 14° C.), agitation almost nil, marine vege- 

 tation extremely abundant. As for deep fauna, there is none of 

 it ; the abundant liberation of carbonic acid gas at the bottom of 

 the crater prevents life being manifested below 20 to 25 metres. 

 The deep fauna of the exterior, on the other hand, is very rich, 

 as indicated by the shells thrown up on the beach. The fauna 

 of Amsterdam Island is identical with that of the exterior of 

 Saint Paul, only the proportion of the different species varies. 



There is, however, a gasteropod of the genus Helix, which is 

 peculiar to the island. 



It was proved, a short time ago, that several kinds of seeds 

 will germinate between pieces of ice. A full investigation of 

 the lower limit of temperature at which plants may germinate 

 has recently been made by M. Haberlandt {Centrall'latt fiir 

 Agricultur chemie). The experiments were upon wheat, rye, 

 barley, red beet, rape, lucerne, poppy, and many other seeds. 

 Several hundred seeds were employed of each species, and every 

 fourteen days the seeds were taken out of the ice-chest, whose 

 temperature was kept constant between 0° and 1°, and examined 

 in a space whose temperature was under freezing-point. In 

 forty-five days a decided beginning of germination was observ- 

 able in eight different species (which are named). In four 

 months it had continued to progress in a minority of these ; the 

 rest had stopped. In fourteen species there was no germination. 

 M. Haberlandt is of opinion that those seeds which can ger- 

 minate at a lower temperature than others of the same species, 

 win give plants that require a less amount of heat for their com- 

 plete development than the others, and thus by artificial sowing 

 in cold spaces a means is to hand of obtaining species soon ripe 

 and needing little heat. Of all the seeds which had remained 

 for four months in the ice-case, only a few were found capable of 

 development when brought into a warmer temperature of 16° C* 



A Universal Congress for hygienic purposes and salvage will 

 be held at Brussels on the occasion of the Exhibition. Tlie 

 Congress will meet from Sept. 27 to Oct. 4. A French com- 

 mittee has been formed of M. Claude Bernard, Admiral Paris, 

 and others. A programme of the questions that are to come 

 before the meeting will be found in the Sanitary Record for 

 August 5. 



The Meteorologische Beobachtungen made at the hydrographic 

 office of the Austrian navy at Pola during June last have been 

 received. They are interesting from the position of Pola being 

 near the southern extremity of the peninsula at the head of the 

 Adriatic. The hourly observations show a strongly-pronounced 

 maximum of wind force from 11 a.m. to 6 P.M., when it is 

 nearly double the force registered from 9 p.m. to 6 a.m. The 

 daily variation in the direction of the wind is equally well 

 inarked. Starting from a point east of south at 5 a.m., it 

 gradually veers to westward, the most westerly point (nearly due j 

 west) being reached at 5 — 6 p.m., after which it gradually shifts 

 back to its starting-point in the morning. The most interesting 

 point in the diurnal curve of the barometer is the occurrence of • 

 the morning maximum at noon, being the time when this phase 

 of the pressure occurs at places situated close to the sea-shore. 

 The maximum temperature occurs as early as from noon to 

 I P.M. 



Mrs. Griesbach has presented to the Lord President of the 

 Council, for the proposed scientific museum, a valuable collec- 

 tion of acoustical apparatus, invented and made by her late 

 husband, John Henry Griesbach. This apparatus is now exhi- 

 bited in the Loan Collection of Scientific Apparatus. 



In a supplement to the Gardener's Chronicle for Aug. 5, is 

 given a well- illustrated description of the Royal Botanic Gardens 

 at Kew, including views in the centre of the palm-stove, the 

 succulent house, the temperate house, &c. 



The additions to the Zoological Society's Gardens during the 

 past week include a Racoon-like Dog I^Nyctereutes procyonides) 

 from Eastern Asia, presented by Capt, W. H. Bingoym ; seven 

 Common Guillemots (Uria troile) and a Kittiwake Gull {Rissa 

 tridactyla), British, presented by Sir H. Dalrymple, Bart. ; a 

 Brown Coati (Nasua nasica) from South America, presented by 

 Mr. R. C. Corfield ; two Hairy Armadillos {Dasypus villosns), 

 bom in the Gardens. 



