170 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



The Science Observer, the organ of the Boston Amateur 

 Scientific Society, contains notes by Henry White, calling at- 

 tention to the importance of observing meteor trains as a 

 means of learning something about the air-currents at high 

 altitudes. The importance of such observations is not to be 

 denied ; but unless several observers at well-located posi- 

 tions unite in such observations, we fear that but little can 

 be deduced relative to air-currents. Were a few persons, 

 located within fifty miles of each other, to systematically ob- 

 serve and compare notes on the motions of cirri, polar bands, 

 and meteor trains, they would soon be in position to materi- 

 ally contribute to meteorology. 



Observations on the direction of the motions of clouds con- 

 tinue to attract increased attention. Besides the apparatus 

 invented by Goddard, Braun, Linss, and others, Marie Davy 

 describes the following, which he has established in the gar- 

 den of the observatory at Mont Souris. It consists essen- 

 tially of a horizontal mirror upon which the sixteen principal 

 compass points are engraved. The observer places his eye 

 so that the image of the cloud appears in the centre of the 

 mirror; he then sets a small cone upon the mirror in such a 

 position that the point of the cone covers the same centre. 

 A few minutes afterwards he brings his eye to the same po- 

 sition, and easily sees in what direction the cloud has moved. 



Linss has observed the motions of the clouds at Darmstadt 

 with his improved form of Braun's nephoscope. He finds 

 that the apparent velocity of cumuli, pallio-cirri, and cirro- 

 cumuli is greater at 8 A.M. than at noon or 4 P.M. Pie finds 

 a constant relation between the directions of the higher 

 clouds as compared to cumuli, and that the changes in the 

 upper strata of air occur at least four hours earlier than in 

 the lower ones. 



The first publication of Dr. Ilildebrandsson on the Move- 

 ments of the Upper Currents has been followed by the pub- 

 lication, at Upsala, of an "Atlas des Mouvements Superieurs." 



Besides this, Rev. Clement Ley has published a series of 

 maps for each day of March, 1S7G. His studies make it prob- 

 able that the stratum of air in which cirrus-clouds occur is at 

 a much higher level over the advancing portion of the cy- 

 clone than over its rear. 



In addition to their memoir on the Distribution of Tempera- 



