METEOROLOGY. 



491 



rotation about the center, such as to cause a true 

 vortex with discharge upward throughout. In 

 the anticyclone on the two outer circles, 750 and 

 1,250 kilometres radius, there is outflow from 

 top to bottom on all sides. Near the center there 

 is inflow at the top, reversal at the middle, and 

 outflow at the bottom, thus causing a reversal 

 of gradients in the interior of the anticyclone. 

 The entire system of high and low areas seems 

 to be constructed by the counterflow, chiefly in 

 the cumulus and strato-cumulus levels, of long 

 currents, due to horizontal convection; the double 

 action of the pressure that is, formation of high 

 and low pressures simultaneously in adjacent dis- 

 tricts being referred to the general circulation 

 of the atmosphere, especially the deflecting and 

 centrifugal forces, rather than to local tempera- 

 ture accumulations. The North American conti- 

 nent is the region where cyclones form in large 

 numbers, and Europe- Asia the region where they 

 dissipate, so that the violent general circulation 

 over the United States in the lower strata, as 

 compared to that of Europe, is chiefly responsible 

 for this excess in the production near or in the 

 United States of the local storms of the northern 

 hemisphere. A careful study of these vectors in 

 all strata up to 11,000 metres, or 7 miles, high 

 shows that there is little disposition to conform 

 to the canal theory of the circulation over the 

 hemisphere namely, that theory which supposes 

 a southward movement in the lower strata from 

 the polar zone toward the tropics, with reversal 

 of the component from east to west at latitude 

 35, together with an overflow northward in the 

 higher strata from the tropics toward the poles. 

 The lower strata do not move southward as a 

 whole, and the observations do not indicate that 

 the higher strata are vigorously moving north- 

 ward; but in each stratum from the surface to 

 the cirrus level about as much air moves north 

 as south, for there are enormous counter-cur- 

 rents passing by one another at the same level, 

 and not over one another at different elevations. 

 This puts a new aspect on the entire problem 

 of the general circulation. 



In closing his paper on Studies of Cyclonic and 

 Anticyclonic Phenomena with Kites Mr. H. Helm 

 Clayton calls attention to the special value of 

 kites for exploring the air up to heights of be- 

 tween 10,000 and 14,000 feet. " Free balloons can 

 not serve so well, because they necessarily drift 

 with the weather conditions by which they are 

 surrounded, and it is impossible with them to 

 record progressive changes and to compare them 

 with changes recorded at a fixed point at the 

 earth's surface beneath. Mountain stations can 

 not serve so well, because the mountains tend to 

 deflect currents upward, mixing air which would 

 otherwise exist in separate strata. This upward 

 movement might perhaps cause an adiabatic rate 

 of cooling in the air when such a rate does not 

 exist in free air. With captive balloons it has 

 teen impossible up to the present time (January, 

 1899) to reach great heights, and it seems in- 

 credible that they should ever be able to with- 

 stand such wind velocities as those encountered 

 by the kites on Nov. 24 and 25 (1898) and yet 

 be held safe by a cable of the necessary light- 

 ness. Captive balloons could, however, be used 

 with great advantage as an adjunct to kites, 

 lifting them when necessary above the light sur- 

 face wind into stronger winds aloft, where they 

 could be automatically detached. (It will be ob- 

 served, in another part of this article, that M. 

 Teisserenc de Bort reports, several months later 

 than the date of Mr. Clayton's paper, having made 

 observations with balloons from his observatory 



at Trappes, France, to heights of from 9,000 to 

 14,000 metres.) 



As a result of his studies with kites, Sept. 21 

 to 24, 1898, Mr. Clayton declare** himself con- 

 vinced, contrary to his previously expressed opin- 

 ion, that the chief, if not all, the features of 

 cyclones and anticyclones can be explained as 

 having their origin within and surrounding these 

 phenomena. In other words, he concludes that 

 the convection theory, with certain modifications 

 which he suggests, is the true one. Prof. W. M. 

 Davis, on the other hand, in a paper read before 

 the Royal Meteorological Society, Feb. 15, af- 

 firmed that it must certainly be made clear to 

 every physical meteorologist that the conven- 

 tional theory of the circulation of the atmosphere 

 as ordinarily stated was seriously incompetent, 

 for the most striking features in the distribution 

 of atmospheric pressure are not accounted for by 

 it. As long as the effect of the winds in modify- 

 ing the distribution of pressure is left out of 

 consideration no broad understanding of atmos- 

 pheric processes can be reached. 



Electricity. Remarking that almost every 

 suggestion that has ever occurred to any one as 

 to the origin of atmospheric electricity "and the 

 part it plays in meteorology has yielded only 

 negative results, and mentioning some of the 

 suggestions, Prof. Cleveland Abbe concludes that 

 the problem is too difficult for immediate solu- 

 tion, and must be left to another generation of 

 physicists. On the simple question of the me- 

 teorological phenomena that are evidently asso- 

 ciated with atmospheric electricity the best phys- 

 icists do not seem as yet wholly clear as to the 

 method of formation of lightning and auroral dis- 

 charges, the phosphorescent glow of the clouds, 

 ball lightning, and other everyday phenomena. 

 Many questions concerning these matters crowd 

 upon our thoughts, " but satisfactory replies can 

 be given only after physicists have invented ap- 

 propriate means of investigation. Meteorological 

 observers may contribute to the solution of the 

 problems by collecting both general data and 

 special observations of exceptional phenomena, 

 but the discussion of the data and the definitive 

 decision by means of experimentation as to the 

 merits of conflicting hypothetical explanations 

 must be left to the leading physicists of the 

 world." 



M. A. B. Chauveau concludes, from comparison 

 of curves of diurnal variations of atmospheric 

 electricity traced at different places, (1) that the 

 influence of the soil, which is greatest in winter, 

 intervenes as a disturbing cause in the variation, 

 and (2) that the general law of variation is rep- 

 resented by a simple oscillation having a maxi- 

 mum in the day and a minimum between 3.30 

 and 4.30 A. M. The author supposes that the 

 principal factor in the influence of the soil is the 

 evaporation of negatively electrified water from 

 the surface of the earth. About thirty different 

 theories have been proposed to explain the diurnal 

 variations in question. 



As the result of seven ascensions made for the 

 purpose of obtaining measurements of the dis- 

 tribution of atmospheric electricity in clear 

 weather and of determining whether the balloon 

 receives electrical charges, Dr. J. Tuma finds 

 that the potential decreases with increasing 

 height. The positive charges are therefore ac- 

 cumulated in the lower strata of the atmosphere. 

 During the last four ascents the author was 

 unable to find that the balloons were electrically 

 charged. 



The appearance on photographs of lightning of 

 what appeared to be dark flashes as well as 



