446 



SCIENTIFIC PECORD FOR 1882. 



as to imply that the sun is most powerful where there are most spots 

 on his surface. Add to this that the spectroscopic observations of 

 Lockyer and others tend in the same direction, as well as such acti- 

 nometric results as we have been able to procure, chiefly through the 

 labors of Mr. Hennessy, at Dehra-Dhoon and Mussoorie. {Nature, 

 XXIII, p. 237.) 



B. Stewart publishes the observations of the height of the river Nile, 

 deduced from a graphic representation of the readings above the zero 

 of the Cairo nilometer, made every five days during the years 1849 to 

 1878, whence he deduced the following approximate relative quantities 

 of water discharged by the river each year: 



Stewart formulates the following conclusions : 



1. The curve representing the heights of the river Nile and that 

 representing the dates of maximum height are very like each other, a 

 maximum height corresponding generally to a late date of maximum 

 rise. 



2. There is also considerable likeness between the Nile curve and 

 that for the river Thames. 



3. There apjjears to be a maximum in these curves at or somewhat 

 after the date of maximum sun-spots, but they have more than one 

 maximum for one sun-spot cycle. 



It would be extremely interesting if this comparison could be still 

 further extended. {Nature, xxv, p. 2G9.) 



Prof. Balfour Stewart communicated to the mathematical and phys- 

 ical section of the British Association for the Advancement of Science 

 a paper on the similarity between meteorological and magnetic weather, 

 by which terms he designates the very variable alternations and beha- 

 vior of the magnetic needles. This is a repetition of a paper read before 

 the Eoyal Society, and shows that in July, August, and December the 

 declination range fluctuation precedes the corresponding temperature 

 range fluctuation by twelve days, whereas in February, March, and Aj)ril 

 it precedes by only five days. 



In a second paper Professor Stewart deals with a supposed connection 

 between the heights of rivers and the number of sun-spots. He finds 

 that the Nile agrees with European rivers, and exhibits a maximum 

 about the time of maximum sun-spots, and predicts that for the cur- 



