594 



NA TURE 



[April i8, 1901 



de Fonvielle mentioned was that the ascents should not be made 

 upon a particular day of the calendar month, as they are at 

 present, but in the lunar month, by preference near the time 

 of New Moon. The interference of moonlight with intended 

 astronomical observations would thus be obviated. 



Dr. Hergesell, president of the International Aeronautical 

 Committee, has sent us an account of the prelimiriary results 



of the international balloon ascents of March 7. Twelve un- 

 manned balloons, three manned balloons and one kite were sent 

 up from various places on the Continent, but the records of 



three of the unmanned balloons were lost. At Vienna a height 

 of 10,000 metres was reached : the lowest temperature recorded 

 was - 62° C. At Moscow the temperatures recorded were 



- 13° C. at starting, - 20° at 4400 metres, and - 4i°"6 at 6650 

 metres. At Trappes, near Paris, one balloon reached 10.820 

 metres and recorded -43° ; the minimum temperature, - 5i°"2, 

 was registered at 8792 metres. A second balloon registered 



- 43°'6 at 10,481 metres and - 53° at 8891 metres. At Strass- 

 burg a height of 10,000 metres was reached, and the minimum 

 temperature recorded was - 52°. Perhaps the most noteworthy 

 record is that of a second balloon from Moscow, - 12° at start- 

 ing, - 15° at 2700 metres ; an inversion of temperature, + 2°, 

 occurred at an altitude of 250 metres. 



The Scientific American states that there is a project on foot 

 for the construction of a movable electric platform on the right 

 bank of the Seine. The platform will be underground, and its 

 length will be about six miles. The route proposed passes 

 under the Avenue de I'Opera, the great boulevards, Boulevard 

 Sebastopol, the Rue Turbigo and the Rue de Rivoli. The 

 new scheme calls for four platforms instead of three, as was in 

 use at the Paris Exposition. The first platform will be 

 stationary, the second will have a velocity of i^ metres a second, 

 the third 3 metres, and the fourth 5 metres. This will enable 

 pedestrians to have a very rapid means of transit afoot in a por- 

 tion of Paris which is greatly encumbered by vehicular traffic, 

 for, as all the locomotion is in one direction, persons can walk 

 very fast on the fourth platform, and will be able to cover a 

 great distance. Some means of transit on the streets mentioned 

 is so necessary that it is probable the scheme will be carried 

 into effect. 



There have been some discrepancies in recent allusions to the 

 1885 experiments carried out at Paris with the navigable balloon 

 La Fiance, Mr. Chanute, in the Engineering Magazine, April 

 1896, referring to speeds of 14 miles an hour, while Sir Hiram 

 Maxim, in the Aeronautical Journal, October 1900, spoke of the 

 speed as about 4 miles an hour, and only a single case of return 

 to the point of departure. A note on this subject appears in the 

 Aeronautical Journal for April, from which it appears that the 

 balloon returned five times to its starting point. On referring 

 to the original article in the Cotuptes re7idus for 1886, we gather 

 that the speed was estimated at from 4 to 6 metres per second, 

 and probably the discrepancy was due to some confusion in regard 

 to the units. 



The Botanical Exchange Club of the British Isles has just 

 issued its annual report for 1899, from which we gather that the 

 number of plants sent in shows a considerable falling off from 

 the average of recent years. It is to be feared that the rival 

 attractions of golf, photography and philately have diverted the 

 attention of many who in former days devoted their spare time 

 to the study of the British flora, and that modern facilities for 

 attending science classes have hardly succeeded in maintaining 

 the interest in field botany and natural history that was shown 

 formerly. Still the report contains many records of interest, 

 notably of the specific and varietal forms of the difficult genus 

 Rubus, which have been studied by the Rev. W. Moyle Rogers, 



NO. 1642, VOL. 63J 



while Mr. F. Townsend has commented on the forms of 

 Euphrasia. The distributor (Rev. W. R. Linton) calls attention 

 to the desirability of members sending not less than ten speci- 

 mens of each plant, but we question whether a too literal 

 interpretation of this recommendation might not lead to the 

 total uprooting of certain rarities. 



Although it has long been known that no- actual gas 

 obeys Boyle's law, attention has been chiefly centred round the 

 divergencies which occur at high pressures. It is true that the 

 behaviour of gases at low pressures has received attention from 

 Siljestrom, van der Ven, Mendeleeff, Amagat, Fuchs, Kraje- 

 witsch, Baly and Ramsay and McLeod, and these experiments 

 have led to the discovery of a discontinuity in the case of oxygen, 

 but the experimental difficulties have led to considerable diver- 

 gencies of results in other respects. An investigation is now 

 described by Prof. A. Battelli in the Nuovo Cimento for January 

 and February, which leads to the following results: — (i) 

 Hydrogen obeys Boyle's law for pressures below one atmosphere 

 down to about 0"2 mm. ; (2) Air deviates slightly from the law 

 between 2 and 5 mm. ; (3) Oxygen exhibits a discontinuity 

 about 07 mm. ; (4) Carbonic anhydride at low pressures is com- 

 pressed more than Boyle's law would indicate, iprobably owing 

 to absorption by the walls of the containing vessel. With 

 the exception of oxygen, and consequently air, the present 

 investigation does not bring to light any anomalies not attribut- 

 able to experimental conditions. On the other hand, the exist- 

 ence of discrepancies, representable by the introduction of a dis- 

 continuous function into the characteristic equation, is not incom- 

 patible with the kinetic theory, but may be attributable to 

 changes in the grouping of the molecules. 



The Accumulator Industries Co. Ltd., has brought out a new 

 primary cell, under the name of the " Cupron-Element," in 

 which the electrodes are plates of zinc and copper oxide and 

 the electrolyte caustic soda, or, for special purposes, caustic 

 potash. The E. M.F. of this combination is low, amounting 

 to only abput o'85 volt ; but this is compensated for by a low 

 internal resistance. It is claimed that the difficulties hitherto met 

 with in the manufacture of a suitable anode (copper oxide) 

 plate have been overcome, and that a coherent and, at the same 

 time, highly porous plate has been obtained which can easily 

 be regenerated when exhausted by simple exposure to the air. 

 The cell has the advantage that there is no local action when on 

 open circuit. To judge from the discharge curves printed in the 

 catalogue, the cell has a high capacity and is capable of giving 

 continuously a steady current. Of course, a primary battery 

 with zinc as the ultimate source of energy can never be really 

 a cheap way of getting current ; but one which gives little 

 trouble, is easily recharged and gives a good steady current, has 

 a considerable range of utility, especially as a means of charging 

 small accumulators. 



To the March number of the American Naturalist Dr. W. H. 

 Dall contributes an account of the morphology of the hinge- 

 teeth of bivalve molluscs, in which the various systems of nomen- 

 clature for these structures that have been from time to time 

 proposed are discussed and contrasted. Many problems in con- 

 nection with the homology and evolution of these structures still 

 await solution. 



In another paper in the American Naturalist for March 

 Messrs. Wheeler and Long discuss the males of certain species 

 of ants of the genus Eciton, with figures of several. These ants 

 have the habit of seizing the larvae and pupae of other kinds of 

 ants, as well as insects of other descriptions, and storing them 

 up in their nests to serve for food as occasion requires. When 

 the colony removes to another nest the booty is carried with 

 the other impedimenta. And if Eciton ants be fed with termites 



