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Art. III. — Account of the Experiments of Morkhinl^ Uidol- 
Firmas, and Gibhs^ on the Jnflueiice of Light in the 
developement (f Magnetism. 
During the last ten 3 ^ears, the curiosity of philosophers 
has been frequently excited by notices in the foreign journals, 
respecting a singular property of the violet light of the spec- 
trum, in virtue of which it is capable of communicating mag- 
netism to small needles, or bars of steel, l^his effect, though 
by no means contradictory to any of the established principles 
of physics, has, in general, been discredited both in this country 
and in France; and those who have readily believed in the ex- 
istence of invisible rays at one end of the spectrum, and of de- 
oxidating rays at the other end, upon the testimony of the few 
eminent men who had repeated the experiments of Herschel 
and of Wollaston, still continue to resist the evidence of the re- 
spectable and distinguished individuals who have actually seen 
needles magnetised by the violet rays. 
Dr Morichini, an ingenious and highly respectable physi- 
cian in Rome^ was the first person who discovered this property 
of the violet rays. At that season of the year when the light 
of the sun is most powerful, he admitted it into his chamber, 
and having formed the coloured spectrum by means of a prism, 
he collected the violet rays in the focus of a convex lens, and, 
by moving the lens parallel to the steel needle, he made the fo- 
cus of the violet rays pass from the middle of one extremity of 
the needle to the other, and always in the same direction, with- 
out touching the other half. By Continuing this operation for 
nearly an hour, the needle was found to be completely magne- 
tised. This remarkable experiment was frequently repeated by 
Morichini with the same success, and was also performed in 
the presence of many Italian and English philosophers. When 
we had the pleasure of meeting our eminent countryman Sir 
Humphry Davy at Geneva in 1814, on his return from Italy, 
he informed us, that he had watched with tlie greatest attention 
the whole progress of one of Morichini’s experiments, and had the 
most thorough conviction of its accuracy. The needle was distinct- 
ly magnetised ; and ihough it was within the limits of possibility. 
