I don't know if Twain was talking about the Cardiff Giant when he wrote "Petrified Giant," but the Cardiff Giant is a wonderful story and might have inspired Twain. A man in the area (can't put my hands on the particulars right now) had a "petrified man" built of gypsum, treated, and interred for a period of time on a Cardiff farmer's property. The farmer, in on the hoax, was to sink a well and "discover" the amazing giant. When it was unearthed, scholars and scientist flocked to Cardiff to study it. Some said it was a genuine petrified man of giant proportions, others said it was a fake. The perpetrator advertised it as genuine, and people came from all over to see it, paying quite a large sum to view it. It was at the Famer's Museum in Cooperstown when I first saw it in 1959, displayed in the ground as it was found. It eventually went "on the road" and ended up on Broadway in NYC where the curious were happy to part with their money to see it. P.T. Barnum had a museum in N.Y.C. at that time and wanted to buy the "giant," whatever it was. The owner refused to sell, so Barnum thought about how one would construct such a "petrified man" if it was indeed constructed. He arrived at the same conclusion as the original builder and built his own Cardiff Giant, the "real one," he claimed. He said the one exhibited down the street was a fake! Both giants played to big crowds. I came upon Barnum's giant, standing, in the Barnum exhibit at old the Danbury Fair before it became a shopping mall. I later saw it at the Barnum Museum in Bridgeport, CT. It was, in fact, a dead ringer for the Cardiff Giant. We know Twain visited the Barnum Museum in NYC because he wrote about it (and dismissed it and its "dried up frogs in glass cases"), so he may have seen it there. Or, as Dr. Dalrymple pointed out, he might have seen it in Cardiff when he was in Elmira. I moved away from the east 23 years agp, so I don't know the fate of either giant since I left. Easy to find out though by contacting Farmer's Museum or City of Bridgeport, CT (they used to have a Barnum Festival in the summer to honor its most famous resident). I'm sure you'll have many replies on this. Elinor Reiss San Diego, CA