In "A Defence of General Funston", which Mark Twain published in the North American Review of May 1902, Twain seems to be referring to a torture method we know of today as "water-boarding". 

The whole article is available at: http://archive.org/stream/northamreview174miscrich#page/612/mode/2up

audio version at:

http://archive.org/details/MarkTwainOntorture