Webster’s Revised Unabridged Dictionary · 1913
Chaldron
Chal′dron (chăl′drŭn or cha̤l′drŭn; 277), n. [OF. chaldron, F. chaudron kettle. The same word as caldron.] An English dry measure, being, at London, 36 bushels heaped up, or its equivalent weight, and more than twice as much at Newcastle. Now used exclusively for coal and coke.
☞ In the United States the chaldron is ordinarily 2,940 lbs, but at New York it is 2,500 lbs. De Colange.