404 JAMES CLEEK MAXWELL. [CHAP. XII. 



needle in the E. S. room and garden. Are the variation com- 

 pass and dipping needle still in the E. S. collection ? 



Cavendish wrote out directions for using the dipping 

 needle for Captain Pickersgill, Captain Bayley, Dalrymple. 



Dalrymple, I find from Poggendorff, was hydrographer 

 to the H.E.I. C. If Cavendish apportioned his instructions 

 according to the capacity of the recipients, then their capaci- 

 ties would be in descending order, Dalrymple, Pickersgill, 

 Bayley. Were any of these F.E.S. ? 



Also, was John Walsh, F.E.S., also M.P. ? 



Do not answer any of these questions which would 

 involve trouble, but I have not here any means of answering 

 them except by the aid of those who are among the records 

 of the past. None of the questions are of vital importance, 

 because I can leave out any statements I have made which 

 are doubtful. Yours very truly, 



J. CLERK MAXWELL. 



Professor Maxwell was frequently invited to join 

 the Victoria Institute, and in March 1875 he received 

 a letter from the secretary conveying the special 

 invitation of the President and Council to join the 

 Society, " among whose members are his Grace the 

 Archbishop of Canterbury, and other prelates and 

 leading ministers, several professors of Oxford and 

 Cambridge and other universities, and many literary 

 and scientific men." The following is all that has 

 been found of a rough draft of his reply : 



SIR I do not think it my duty to become a candidate 

 for admission into the Victoria Institute. Among the objects 

 of the Society are some of which I think very highly. I 

 think men of science as well as other men need to learn 

 from Christ, and I think Christians whose minds are scientific 

 are bound to study science that their view of the glory of 



