Copy letter from Herbert Rix, to Professor Joseph Norman Lockyer, Fellow of the Royal Society 'Dear Sir, I am sending you proof of your spectrum to paper on Electrolytic Iron. I am afraid they have made it too tall, though I told them it was for Phil Trans. ['Philosophical Transactions of the Royal Society'] & gave them particulars. But if you will criticise it in other respects I will see how the difficulty may be met. It is done by the Woodbury Type Co (Eyre & Spottiswoode's) who did your last spectrum. I am, yours truly, Herbert Rix Asst. Sec. RS. [Assistant Secretary, Royal Society]'. 9 April 1894