The Fisheries exhibit occupies an entire wing of the 3-building exhibit. Thirty-two big tanks lit from behind in darkened rooms show fresh and salt-water fish used for food, like king crabs, sturgeon, eels, trout, diamond-back terrapins. Salt water is brought in by tank car from Woods Hole, Massachusetts and chilled under the building by ice. The Post Office exhibit contains samples of all the United States stamps ever produced, a display made possible by loans from private stamp collectors.