All 3 Uses of

testimony

in

Moby Dick

But fortunately the special point I here seek can be established upon testimony entirely independent of my own.†
Chpt 43-45 *

But as all else in him thinned, and his cheek-bones grew sharper, his eyes, nevertheless, seemed growing fuller and fuller; they became of a strange softness of lustre; and mildly but deeply looked out at you there from his sickness, a wondrous testimony to that immortal health in him which could not die, or be weakened.†
Chpt 109-111

…actually caulked and pitched their chests, and filled them; it was humorously added, that the cook had clapped a head on his largest boiler, and filled it; that the steward had plugged his spare coffee-pot and filled it; that the harpooneers had headed the sockets of their irons and filled them; that indeed everything was filled with sperm, except the captain's pantaloons pockets, and those he reserved to thrust his hands into, in self-complacent testimony of his entire satisfaction.†
Chpt 115-117

Definition:

(testimony)
something that serves as evidence -- especially a statement at a trial or hearing