Barretter Both answers for 50Ac and 39 Down are affected by the theme. Remember : "Numbers in brackets refer to grid entries". On that basis 50 Ac is a fairly common word for "exhausted" whilst 39 Down IS obscure, the cryptic reference being for a word for tide (3) follwed by a river (4). The cryptic part of 51 Ac is an old word for ON plus a word for throne ("....this castle hath a pleasant ______ ") but with the E then shoved to the end. Thanks for TYE, by the way.