From the record there appears to be some confusion over the exact manner in which defense counsel desired to prove Mrs. Wilkinson's mental incompetence. The petition was inadmissible because it constitutes hearsay, Cox v. State, 36 Ala. App. 99, 102, 52 So.2d 826 (1951), and insanity may not be proven by hearsay. Dickinson v. State, 228 Ala. 28, 29, 152 So. 29 (1934).