The puzzle was to place your pencil on the A at the top of the amulet and
count in how many different ways you could trace out the word
"Abracadabra" downwards, always passing from a letter to an adjoining
one.
A
B B
R R R
A A A A
C C C C C
A A A A A A
D D D D D D D
A A A A A A A A
B B B B B B B B B
R R R R R R R R R R
A A A A A A A A A A A
"Now, mark ye, fine fellows," said Sir Hugh to some who had besought him
to explain, "that at the very first start there be two ways open:
whichever B ye select, there will be two several ways of proceeding
(twice times two are four); whichever R ye select, there be two ways of
going on (twice times four are eight); and so on until the end. Each
letter in order from A downwards may so be reached in 2, 4, 8, 16, 32,
etc., ways. Therefore, as there be ten lines or steps in all from A to
the bottom, all ye need do is to multiply ten 2's together, and truly the
result, 1024, is the answer thou dost seek."