Miscellaneous Kotices hy Prof. J. F. Dana. 163 



however, were observed in the woods, and in small yards 

 and other inclosures, sheltered from the wind, thus indica- 

 ting that their formation commenced in the atmosphere. 

 Similar balls were observed in most of the contiguous towns. 

 Their appearance on the river Androscoggin was extreme- 

 ly interesting. 



Art. XII. — Miscellaneous Notices by Prof. J. F. Dana, of 



Dartmouth College. 



1 . Connexion of Electricity^ Heat, and Magnetism. 



The notices which have appeared in your Journal on the 

 connexion between Electricity and Magnetism have indu^ 

 ced me to make some experiments, and as they tend to con- 

 firm those made by Mr. Bowen, I will mention them. The 

 apparatus consisted of the Leyden bottle and glass tubes sur- 

 rounded by brass wire. I have not yet had opportunity to 

 repeat any of the experiments with the galvanic battery, ex- 

 cept in one instance when a piece of steel was inclosed in a 

 glass tube half an inch in diameter and surrounded by a spi- 

 ral coil of brass wire, and the influence from ray battery, 

 consisting of two hundred plates six inches square, was pas- 

 sed through the coil for one minute, the steel did not appear 

 2ii first to be affected, hut the next day was found feebly mag- 

 netic — this experiment was made at the same time on anoth- 

 er and similar piece of steel with the same result. With 

 common electricity I have been more fortunate. When the 

 charge from a small Leyden jar was passed through the coil 

 the steel inclosed in the tube was uniformly rendered mag- 

 netic, if the coil passed from right to left the south pole was 

 always found on the negative end, whether the jar was char- 

 ged with positive or negative electricity ; when the coil pas- 

 sed from left to right, the north pole was uniformly formed 

 next the negative, whether the jar was charged with posi- 

 tive or negative electricity. These two experiments con- 

 firm those of Mr. Bowen. In using a tube surrounded by a 

 coil passing from right to left for one half its length, and then 

 in the contrary direction, as in Mr. B's. experiment, I found, 

 when the jar was charged with positive electricity, and the 

 eoil began to pass from right to left on the positive, that both 



