From Twain scholars Baetzhold (Butler Univ.) and McCullough (Elmira College Center): an omnibus of Twain's skeptical writings, mostly fiction, about the Bible, Darwin, and evolution, along with similar 19th-century nailbiters questioning American Christianity. While many pieces here are new to print, others been seen before but scattered about. The present collection--spanning four decades (1871-1910)--is both a genuine service to Twain lovers and one showing Twain at his most charming and witty. Refreshened here is the first version of ``Adam's Diary,'' which now has a unity that much outshines the more commonly reprinted version set at Niagara Falls (cuts from that one are stored in the appendix). While the companion pieces ``Eve's Diary'' and ``Eve's Autobiography'' show Twain at his tenderest, many entries spring from tragedies in his own life. One must remember when reading Twain's mischief just how fresh and ``unprintable'' this material once was, something like The Satanic Verses of its day.