Intelligence and Miscellaneous Articles* 24*7 



the last ten or eleven months in any way have arisen from solar 

 magnetic disturbance, which there is some reason perhaps for sup- 

 posing, and this, again, from the position of the planets above-named 

 in conjunction, there is reason to fear there may not be much 

 amelioration in our weather for some months to come, seeing that 

 Venus, Jupiter, and Saturn will remain some time longer in much 

 the same relative position. 



M. Rudolph Wolf of Berne has shown that those years remark- 

 able for abundance of solar spots have also been more than com- 

 monly rich in aurora? boreales. The great auroral display at the 

 commencement of September 1859, occurring about the time for 

 the return of sun-spot maximum, and which seems to have been 

 visible over the greater portion of both hemispheres, appears to have 

 been the precursor of a great meteorological disturbance : in Eng- 

 land and Northern Europe more than an average amount of cold, 

 wind, and rain have prevailed ever since ; in North America and India 

 more than an average amount of drought and heat. The opinions 

 of philosophers differ respecting the influence of a paucity or an 

 abundance of solar spots upon the temperature and seasons of the 

 earth; the probability is, there is simply a general disturbance, 

 arising from increase of (solar) magnetic influence, which may pro- 

 duce greater heat and dryness in one part of the globe, and more 

 cold and rain in other parts. 



I have merely hazarded these few remarks in the hope of drawing 

 further attention to such interesting and important topics. 



Yours respectfully, 

 Manchester, 23rd August, 1860. Robert P. Greg. 



ON THE PHENOMENA OF HEAT WHICH IN CERTAIN CASES ACCOM- 

 PANIES THE VIBRATORY MOTION OF BODIES. BY M. LE ROTJX. 



The author observed that, in attempting to create a nodal line in a 

 body at a place at which it would not naturally be produced, there 

 is a disengagement of heat at this place, this being the form under 

 which the forces evoked by the vibratory motion manifest themselves. 



The experiment may be made by clamping an elastic plate of any 

 material at some distance from one end, and presenting the other to 

 a toothed wheel. The heat produced is great enough to be per- 

 ceptible to the hand. 



The same fact may also be observed by soldering a small piece of 

 brass to a steel spring, and then binding one end of the galvanometer 

 to the steel and the other to the brass. When the spring is made 

 to vibrate, the motion, which is obstructed at the place where the 

 brass is, creates an elevation of temperature which produces an 

 electric current. 



It is important to compare this experiment with those of MM. 

 Sullivan and Ermann*. In Le Roux's experiment the place of the 

 soldering is not directly excited, and consequently all effects of 

 friction are eliminated. If his results appear to confirm those 



"* De la Rive, Traite d'Electricite, vol. ii. p. 574. 



