Just find a mistake in Carl Franklin's book British Napoleonic Field Artillery.

In p. 35, he said

Muller gave the following casualty figures from a 6-pr gun against cavalry:
1,600 yards to 800 yards four killed, two wounded
800-400 yards six killed, four wounded
Under 400 yards nine killed, twenty-three wounded
Against infantry the figures were:
1,600-1,200 yards
1,200-800 yards
800-400 yards
Under 400 yards
four killed, four wounded
eight killed, two wounded
sixteen killed, ten wounded
thirty killed, ninety wounded

You'll find a similar table in Imperial Bayonets, 1996, p. 271.

However, Muller never wrote this content. The nearest figures come from his The Elements of the Science of War, vol. 2, p. 165-166.
http://books.google.com/books?id=KCJEAAAAYAAJ&pg=PA165

But, Muller's figures are in 'paces', not 'yards', and there exist some discrepancies in figures, how could that happen?
If you read Hughes' Firepower Weapons Effectiveness On The Battlefield, 1630-1850, you will find the answer in p. 44. Hughes just used yards instead of paces, but he did give the correct chart. However, Franklin might only read that chart (The Elements of the Science of War is not in his Bibliography), and think the column of wounded are over the column of killed, so he got a lesser number of wounded, but roughly the same number of killed.