In answer to yours of the 20th inst. [instant], I find that our "Philosophical Transactions" ['Philosophical Transactions of the Royal Society'] are too large in size to come within the limits allowed for book-post. I am writing to our Agents to see whether any more expedious way of sending the parcel can be devised.
I am, yours truly,
Asst. Sec. R.S. [Assistant Secretary, Royal Society]'.