8. The control method according to claim 7 , wherein each of the second and subsequent documents is subjected to a pre-separation control which first drives the drawing device to rotate in a direction away from a reading position and then drives the drawing device to rotate in the opposite direction to convey the document toward the reading position.
9. The control method according to claim 8 , wherein the control to perform the high-speed conveyance and the pre-separation is determined on the basis of whether or not the first document detector has detected the trailing end of the document preceding each of the second and subsequent documents.