vi WORK AT MANCHESTER 131 



that time will justify me and put the parsons in the 

 wrong. 



Have you a good large screen, or will it be necessary for 

 me to send one down ? 



Can I address the audience from the side of the Hall ? it 

 looked a long way to the end when I heard Huxley. 



I hardly think he was heard at the end. 



Yours truly, 



JOHN TYNDALL. 



On July 4th, 1863, I married Lucy, youngest daughter 

 of Edmund Potter, Esq., F.R.S., of Camfield Place, 

 Herts, for many years M.P. for Carlisle. This was 

 indeed for me " The Glorious Fourth " ! Through 

 joy and sorrow, the common lot of mankind, she has 

 now for more than forty years been to me a true and 

 faithful friend, a loving presence in all our halcyon days 

 and a tower of strength in times of trouble. 



The same year brought me another privilege, which, 

 though less vital, was still a welcome one, the Fellow- 

 ship of the Royal Society. 



My first Friday evening discourse at the Royal Insti- 

 tution was given on April 4th, 1856, on the " Chemical 

 Action of Light," at the suggestion of my friend Brodie 

 (afterwards Sir Benjamin), who was at that time con- 

 nected with the Institution. I was very young, being 

 only twenty-three, and my topic, I am afraid, was not 

 one of much general interest. The subject of my next 

 lecture, on March ist, 1861, was one which, however, 

 had aroused the attention of the civilised world, i.e., 

 " Bunsen's and KirchhofFs Discoveries in Spectrum 

 Analysis." In 1862 I gave a course of three lectures 

 on " Spectrum Analysis " at the Royal Institution, 

 which I repeated at the London Institution in 1864. 

 On Friday, May 22nd, 1863, I gave a further lecture 

 on the direct measurement of the chemical action of 



K 2 



