Meantime, the camera being finished, Mr. Wolcott, after reading for himself Daguerre's method of iodizing, prepared two plates, and placing them in the camera, guessed at the required time they should remain exposed to the action of the light; after Mercurializing each in turn, and removing the iodized surface with a solution of common salt two successful impressions were obtained, each unlike the other!
"American Handbook of the Daguerrotype"
Samuel D. Humphrey