In the Christian religion,why were ashes originally sprinkled on the top of people's heads on Ash Wednesday instead of on the forehead?

This site gives the history of the use of ashes on Ash Wednesday.

http://www.wf-f.org/AshWed.html#anchor2360581

http://www.americancatholic.org/Newsletters/CU/ac0204.asp

Thank you Gurublue!

You're welcome! I'm glad I could help. If you have any more questions, feel free to ask!