Copy letter from Herbert Rix, to Dr Frederick William Edridge Green, 6 Ravensfield Villas, Hendon, N.W. 'Dear Edridge-Green, I have not answered your letter of December 19th until now because I had no opportunity of consulting the Officers and I felt doubtful whether the question you asked was one that could be officially answered. I am now instructed to say that the matter is not one upon which we can officially advise you, and, as I personally have had no experience whatever of dealing with instrument-makers, I am sorry to say that in my unofficial capacity I cannot say what course you had better pursue. I am, yours truly, Herbert Rix Asst. Sec. R.S. [Assistant Secretary, Royal Society]'. 3 January 1896