John Nevil Maskelyne,
Sharps and Flats
“ In a round game, when it is your turn to deal, you may read the cards as you deal them; and in this way know the hands of your opponents, or at any rate the principal cards. In a single-handed game you can remember the whole of your antagonist's cards, but with more than two players it is not advisable to attempt to commit to memory more than one hand. That, preferably, should be the hand of the 'flattest man,' the 'greatest mug,' the man who is playing highest, or your most dangerous opponent. With a little practice the top card of the pack can be read, just before it is dealt. ”
