Ban goc (Tiếng Anh)

LETTER CCXXXVIII LONDON, February 2, 1759 MY DEAR FRIEND: I am now (what I have very seldom been) two letters in your debt: the reason was, that my head, like many other heads, has frequently taken a wrong turn; in which case, writing is painful to me, and therefore cannot be very pleasant to my readers. I wish you would (while you have so good an opportunity as you have at Hamburg) make yourself perfectly master of that dull but very useful knowledge, the course of exchange, and t