The Collaborative International Dictionary of English v.0.48:

Attemperate \At*tem"per*ate\, a. [L. attemperatus, p. p. of
   attemperare. See Attemper.]
   Tempered; proportioned; properly adapted.
   [1913 Webster]

         Hope must be . . . attemperate to the promise.
                                                  --Hammond.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Attemperate \At*tem"per*ate\, v. t.
   To attemper. [Archaic]
   [1913 Webster]