Contractual penalty clause validly enforced as agreed sum for breach of contract without prior notice requirement.

The court upheld the contractual penalty clause, ruling it validly enforceable as an agreed sum for breach. The plaintiff argued the clause was clear and specific, while the defendant claimed it constituted an excessive sanction. The court decided the clause was lawful because it strictly defined the obligation to pay a fixed amount upon non-performance, aligning with statutory requirements for such penalties.