The Color of Magic: Two Eyes, Not Four!

pg 16

Blind Hugh is standing on the wharves when a ship comes in with a fabulously wealthy passenger, Twoflower.

Blind Hugh is of course a takeoff on Blind Pew, from Robert Louis Stevenson's Treasure Island.

Blind Hugh greets the stranger, and "found himself looking up into a face with four eyes in."

Twoflower does not have four eyes - he's wearing glasses! Which apparently no one in Ankh Morpork has seen before.

Twoflower consults a Phrasebook as he talks to Blind Hugh, another take off on the poor unwary tourist.

The tavern to which Blind Hugh brings Twoflower is the Broken Drum. In subsequent books, it will be Mended.