17. Delay.

The carrier must deliver the goods at the agreed time. In some cases this obligation will be strict, so that a carrier who gives an unqualified promise as to the time of delivery may be liable for late delivery irrespective of reasonable care on his part1. In such a case, only those events which frustrate the contract will relieve the carrier2. Often, however, a promise to deliver at a particular time will be construed as requiring the carrier to exercise reasonable effort or care to meet the promised date: in such a case, the carrier will not be liable