Board of trade contracts

241.24 Board of trade contracts. No contract for the future purchase, sale, transfer or delivery of personal property through a board of trade or organized commodity exchange is void when either party thereto intends, in good faith, to perform the same; and an intention on the part of either not to perform any such contract does not invalidate it if the other party in good faith intends to perform the same. No such contract is void because the vendor was not, at the time it was made, the owner of the property contracted to be sold; and in any action by either party for the enforcement of its terms or to recover damages for a breach thereof it is incompetent to show in defense, by any extrin-