While training as a cub pilot, Mark Twain convinced his brother Henry to pursue a career on the river.  Henry was fatally scalded when the boilers of the packet he was working on exploded.  Henry died on 21 Jun 1858.   The packet was the str Pennsylvania.  Twain held himself responsible for his younger brother’s death for the rest of his life.

The str Pennsylvania, which originally ran from Pittsburgh to Cincinnati, was involved in the Wheeling Bridge Case.  After that infamous gesture and response from the Wheeling landing, the str Pennsylvania went into the St Louis and New Orleans trade.  Her boilers exploded near Helena, AK on Sunday morning 13 Jun 1858.  Henry Clemens suffered for more than a week before succumbing to the pain of his burns.