The Collaborative International Dictionary of English v.0.48:

Arraswise \Ar"ras*wise`\, Arrasways \Ar"ras*ways`\, adv. [Prob.
   a corruption of arriswise. See Arris.]
   Placed in such a position as to exhibit the top and two
   sides, the corner being in front; -- said of a rectangular
   form. --Encyc. Brit. Cussans.
   [1913 Webster]