We sent you Postal Orders, with an account originally made out to Prof. [Professor] Silvanus Thompson but altered to our name, in payment of 12/6 for delivering instruments here. We do not seem to have received the receipt. We think possibly you sent it to Prof. Thompson by mistake. Can you kindly send us a duplicate? I believe there is still an item of 10/6 outstanding: if you will send me an invoice for the same I will pay it.
Asst. Sec. R.S. [Assistant Secretary, Royal Society]'.