To-day we know that Abracadabra was the supreme deity of the Assyrians, and this curious arrangement of the letters of the word was commonly worn in Europe as an amulet or charm against diseases. 

But Sir Hugh had never heard of it, and, regarding the document rather seriously, he sent for a learned priest.
"I pray you, Sir Clerk," said he, "show me the true intent of this strange writing."

"Sir Hugh," replied the holy man, after he had spoken in a foreign tongue with the stranger, "it is but an amulet that this poor wight doth wear upon his breast to ward off the ague, the toothache, and such other afflictions of the body."

"Then give the varlet food and raiment and set him on his way," said Sir Hugh. 
"Meanwhile, Sir Clerk, canst thou tell me in how many ways this word 'Abracadabra' may be read on the amulet, always starting from the A at the top thereof?"

Place your pencil on the A at the top and count in how many different ways you can trace out the word downwards, always passing from a letter to an adjoining one.

See answer