He was also sole illustrator of Twain 's " Sketches , New and Old " and primary illustrator of " Roughing It " and " The Innocents Abroad " .
Head entity: the innocents abroad Q1211101 25 26 27
Tail entity: roughing it Q3576767 20 21
Relation (head \u2192 tail): P156
Inverse relation (tail \u2192 head): P155