“From the general tenour of the results that I have stated, it appears reasonable to conclude that there exists in the fluoric compounds a peculiar substance, possessed of strong attractions for metallic bodies and hydrogen, and which combined with certain inflammable bodies forms peculiar acids, and which in consequence of its strong affinities and high decomposing agencies, it will be very difficult to examine in a pure form, and for the sake of avoiding circumlocution, it may be denominated _fluorine_, a name suggested to me by M. Ampère. “It is easy to perceive in following the above theory, that all the ideas current in chemical authors respecting the fluoric combinations, must be changed. Fluor-spar, and other analogous substances, for instance, must be regarded as binary compounds of metals and fluorine.” Davy’s views are now part of current chemical doctrine, and his previsions as to the nature of fluorine and its extraordinary chemical activity have been verified in the most striking manner by the admirable investigations of Moissan. CHAPTER IX. DAVY AND FARADAY--IODINE. The year 1813 is memorable in the history of the Royal Institution, from the fact that Faraday’s long and honourable association with it dates from that time. The circumstances which led to this connection were subsequently stated by himself in the following letter to Dr. Paris:-- “Royal Institution, _Dec. 23rd, 1829_. “MY DEAR SIR,--You ask me to give you an account of my first introduction to Sir H. Davy, which I am very happy to do, as I think the circumstances will bear testimony to his goodness of heart. “When I was a bookseller’s apprentice, I was very fond of experiment and very averse to trade. It happened that a gentleman, a member of the Royal Institution, took me to hear some of Sir H. Davy’s last lectures in Albemarle Street. I took notes, and afterwards wrote them out more fairly in a quarto volume. “My desire to escape from trade, which I thought vicious and selfish, and to enter into the service of Science which I imagined made its pursuers amiable and liberal, induced me at last to take the bold and simple step of writing to Sir H. Davy, expressing my wishes, and a hope that, if an opportunity came in his way, he would favour my views; at the same time I sent the notes I had taken at his lectures. “The answer, which makes all the point of my communication, I send you in the original, requesting you to take great care of it, and to let me have it back, for you may imagine how much I value. “You will observe that this took place at the end of the year 1812, and early in 1813 he requested to see me, and told me of the situation of assistant in the laboratory of the Royal Institution, then just vacant.