When Mark Twain was seventeen he went back to the home of his boyhood resolved to become a pilot on the Mississippi. How he learnt the river he has told us in 'Life on the Mississippi, ' wherein his adventures, his experiences, and his impressions while he was a cub-pilot are recorded with a combination of precise veracity and abundant humor which makes the earlier chapters of that marvelous book a most masterly fragment of autobiography. The life of a pilot was full of interest and excitement and opportunity, and what young Clemens saw and heard and divined during the years when he was going up and down the mighty river we may read in these pages