Two possible connections b/ Merlin's Cave in CY and McDowell's Cave (McDougal's in TS): 1)in 1840's cave's owner placed body of dead 14yr old girl in cave to see if it would petrify--memory may have suggested Yankee's long sleep; 2) McDowell also stockpiled cannon and small arms in cave. Is McDowell's Cave prototype of Merlin's rather than English one. Some study of the topography around the Mark Twain Cave may yield answer to Sand Belt question.