1845.ÆT.53–54.

The second period of Faraday's electrical work lasted ten years. The discoveries he made were published in the ‘Philosophical Transactions.’ They constitute from the nineteenth to the thirtieth series of his ‘Experimental Researches in Electricity.’ The three great results which he obtained he called ‘the magnetisation of light,’ ‘the magnetic condition of all matter,’ and ‘atmospheric magnetism.’

Faraday's reputation at this time was so great that it added to the renown which followed the publication of each of these new discoveries; but great as the results were, they will not at the present time rank with the three great discoveries of ‘magneto-electricity,’ ‘voltaic induction,’ and ‘definite electro-chemical decomposition,’ which made the glory of the first period of the ‘Researches in Electricity.’

In the beginning of 1845 Faraday worked on the condensation of gases; on August 30 he began to experiment on polarised light and electrolytes, a subject which in 1833 had given ‘no result.’ After three days he worked with common electricity, trying glass, heavy optical glass, quartz, Iceland spa. Still he got no effect on the polarised ray. On September 13 he writes: ‘To-day worked with lines of magnetic force, passing them across different bodies transparent in different directions, and at the same time passing a polarised ray of light through them, and afterwards examining the ray by a Nichol's eye-piece or other means.