546 



SCIENTIFIC RECORD FOR 1883. 



August and September are the months of greatest frequency for Japan- 

 ese typhoons, but September and October for Chinese. The velocity 

 of movement is slowest near the apex, and is rather slower in the China 

 than in the sea of Japan. (Z. 0. G. M., xvn, p. 336.) 



Dr. Assman, director of the local meteorological station at Magde- 

 burg, whence special weather predictions are daily issued, has paid 

 special attention to the phenomena of local thunder storms, and urges 

 the establishment of more numerous stations whence data may be de- 

 rived for plotting the phenomena of the storm as a whole at short in- 

 tervals of time. His continuous records of temperature and wind show 

 sudden oscillations of temperature that seem to him to indicate local 

 cyclonic movements. (Z. 0. G. M. xvn, p. 337.) 



A. Eichter has analyzed the observation of thunder-storms during 

 four years, 1877 to 1880, at seven stations in the department of Glatz. 

 A thunder-storm is considered to have passed over any locality when 

 the interval between the thunder and lightning is not greater than sixty 

 seconds. The annual and daily periodicity is shown in the following 

 table of frequency : 



Ii. 



III. 



Hours. 



12 - 3a.m 



3 a. m.- 6a. m 



6 a. m.- 9 a. m 



9 a. m.-12noon 



12 -3p.m 



3 p.m.- 6 p. m 



6 p. m.- 9p. m 



9 p. m. -12 midnight 



Total 



Uniform high pressure 3.7 



Central region of maximum 2.1 



Near a maximum 11.1 



Zone between maximum and minimum . 43. 



Near a minknuin 18.5 



Central region of minimum 4.7 



Uniform low pressure 2. 8 



The distribution according to the location of the centers of maximum 

 and minimum pressure is shown by the third table. When the tem- 

 perature is above or below the normal, the storms occur as follows : 



0-2° below normal 17.9 



0-2° above normal 27.3 



2-4° above normal 26. 9 



4-6° above normal - 12.5 



(Z. 0. G. M., xvii, p. 329.) 

 Dr. W. Holtz describes ingenious experiments to prove that tornadoes 

 and waterspouts, &c, are caused by electricity, and are not the me- 

 chanical effect of rotation of a portion of the atmosphere. He however 

 quotes equally beautiful experiments of Xavier de Maistre (Bibl. Uni- 

 vers, 1832, vol.Li ; Silliman's Amer. Jowr., 1834, XXV), that fully support 

 the mechanical theory. (Z. O. G. M., xvn, p. 370.) 



