Dear Sir

It is extremely kind in you to have taken the trouble of informing me of the error which you have discovered.¹ As soon as more copies are printed off, I will hunt up my notes & endeavour to find out how the horrid error arose. It is just possible that the amount per square yard was 1 lb 14$\frac{1}{2}$ oz instead of 1 : 13$\frac{1}{2}$ oz. All the calculations were checked by some member of my family;² but somehow I never escape blunders.

Two others have been discovered, almost as bad as that which you have discovered, excepting that they are so flagrant they c^d. deceive no one.³

Again thanking you, I remain, Dear Sir | Yours faithfully | Ch. Darwin