78 THE POPULAR SCIENCE MONTHLY. 



to me and saved me. I could trust a fact, and always cross-examined an asser- 

 tion. So, when I questioned Mrs. Marcet's book, by such little experiments as I 

 could find means to perform, and found it true to the facts as I could understand 

 them, I felt that I had got hold of an anchor in chemical knowledge, and clung 

 fast to it. Thence my deep veneration for Mrs. Marcet first as one who had 

 conferred great personal good and pleasure on me ; and then as one able to con- 

 vey the truth and principle of those boundless fields of knowledge which con- 

 cern natural things to the young, untaught, and inquiring mind. 



You may imagine my delight when I came to know Mrs. Marcet personally; 

 how often I cast my thoughts backward, delighting to connect the past and 

 present; how often, when sending a paper to her as a thank-olfering, I thought 

 of my first instructress, and such thoughts will remain with me. 



Henry wrote on the inside of tlie cover of Gregory's work the fol- 

 lowing words : 



TIjIs book, although by no means a profound work, has, under Providence, 

 exerted a remarkable influence on my life. It accidentally fell into my hands 

 when I was about sixteen years old, and was the first book I ever read with at- 

 tention. It opened to me a new world of thought and enjoyment ; invested 

 things before almost unnoticed with the highest interest ; fixed my mind on the 

 study of nature, and caused me to resolve at the time of reading it that I would 

 immediately commence to devote my life to the acquisition of knowledge. J. H, 



Each of these philosophers worked with simple instruments mostly 

 constructed by his own hands, and by methods so direct that he ap- 

 peared to have an almost intuitive perception into the workings of 

 nature ; and each gave great care to the composition of his writings, 

 sending his discoveries into the world clothed in simple and elegant 

 English. 



Finally, each loved science more than money, and his Creator more 

 than either. 



There was sympathy between these men, and Henry loved to dwell 

 on the hours that he and Bache had spent in Faraday's society. I 

 shall never forget Henry's account of his visit to King's College, Lon- 

 don, where Faraday, Wheatstone, Daniell and he had met to try and 

 evolve the electric spark from the thermopile. Each in turn at- 

 tempted it and failed. Then came Henry's turn. He succeeded ; 

 calling in the aid of his discovery of the effect of a long inter-polar 

 wire wrapped around a piece of soft iron. Faraday became as wild as 

 a boy, and, jumping up, shouted, "Hurrah for the Yankee experi- 

 ment ! " 



And Faraday and "Wheatstone reciprocated the high estimation in 

 which Henry held them. During a visit to England, not long before 

 AVheatstorie's death, he told me that Faraday an4 he had, after Hen- 

 ry's classical investigation of the induced currents of different orders, 

 written a joint letter to the council of the Royal Society, urging that 

 the Copley medal, " that laurel-wreath of science," should be bestowed 

 on Henry: On further consultation with members of the council, it 



