1T2 Scientific InteUigence. — Mechanical Phihsophp. 



he found that in the course of five minutes, the wire when presented 

 to a ' magnetic needle, manifested very decidedly the existence of 

 poles. 



The violet ray changed or reversed a well marked pole in a soft 

 iron needle* 



The red, yelloW) orange and green ray produced no alteration 

 whatever in a magnetic needle, nor in one which had no sensible 

 magnetism. 



A soft iron wire, covered with a coat of oxide, and strongly mag- 

 iletized, exposed to the violet light, in three minutes, had its south pole 

 transformed to a north pole. 



A soft wirCj magnetized, being bent, and both ends exposed to the 

 violet ray, in ten minutes, both ends became north. 



If the wire was oxidized, this change was effected in five minutes. 



These experiments were so often repeated as to leave no doubt of 

 the magnetizing property of the violet ray. 



In the Course of his investigations. Prof. Z. ascertained that iron 

 obtained from a sulphurous mine, could not be thus magnetized, 

 nor was it easy to produce much effect upon iron highly tempered. 



At low temperatures, also, such as 6'^ R. 0, + 10°, the results are 

 Very equivocal. But at + 20°, Centig. the temperature of Mrs. 

 Somerville, or at 25° or 26°, R. that of Prof. Z. the resuhs are very 

 striking. 



If the middle of the needle be placed in the violet ray, the effects 

 are weak or uncertain. 



Perceiving that the carburets* could acquire magnetism and not the 

 sulphurets*— that needles artificially oxidized, presented the phenom- 

 enon in question more promptly than those which are not so, and that 

 the effect increases or diminishes with the temperature, Prof. Z. is 

 Confirmed in the opinion that the action of the violet ray is chemical. 

 The light of a candle gave him, in three fourths of an hour, a slight 

 degree of magnetism, but the violet light of the moon had no effect. 

 The latter was tried, however, at a temperature not exceeding 6°, R^ 



Prof. Z. finds his needles retaining their magnetism, at the end of 

 eight months.— jBi6. Univ. Mai) 1829. 



* Of iron.— Ed. 



