1834  (1961)  . . . trees have to be split and hollowed out into troughs to form the roof. . . .
1863  The Yankee took the adze from his hand . . . and set about hollowing troughs very rapidly.
1961  The walls are chinked with "slats and moss" and roofed with "wooden troughs." The interpretation for the wooden troughs for roofing is perfectly clear. They consisted of halved cedar logs hollowed out and laid alternately with the trough up and inverted. . . .