This essay will provide a summary of the well-known contract law case of *Hartley v Ponsonby* (1857). The purpose is to look at the facts of the case, the legal issue that the court had to decide, and the final judgment that was given. The case is an important one in business law because it deals with the rule of consideration, specifically in situations where a party is already under a pre-existing contractual duty. It is often taught alongside *Stilk v Myrick* (1809) because it shows an exception to the rule established in that earlier case.
The Facts of the Case
The case concerned a ship called the `Mobile`. The claimant, Hartley, was a sailor who had signed on as part of a 36-man crew for a voyage. The journey was from Liverpool to Port Phillip in Australia, then on to other ports, and eventually ending in Bombay. When the ship arrived at Port Phillip, a large number of the crew, seventeen in total, deserted. This left only nineteen crew members to continue the voyage. Of these nineteen, only a small number, about five, were experienced able seamen.
The defendant, Ponsonby, was the master of the ship. Because so many crew had left, sailing the ship to Bombay would be much more dangerous than it would have been with a full crew. The remaining sailors, including Hartley, were therefore reluctant to carry on. Ponsonby promised to pay Hartley and the other remaining seamen an extra £40 if they would agree to sail the ship to Bombay. The sailors agreed to this and worked the ship to Bombay. When they arrived, however, Ponsonby refused to pay the extra money he had promised. Hartley then sued Ponsonby to get the payment.
The Legal Issue
The main legal problem for the court to sort out was whether there was good consideration for the captain’s promise of extra pay. The general rule in contract law, established in cases like *Stilk v Myrick* (1809), is that performing a duty you are already legally obliged to perform under an existing contract is not good consideration for a new promise from the other party.
In Hartley’s situation, he already had a contract to serve on the ship for the whole voyage, all the way to Bombay. Ponsonby’s defence was that Hartley and the other sailors had not provided any new consideration for the promise of extra money, because they were just doing what they were already supposed to do. So, the court had to decide if the sailors’ agreement to continue with the voyage after the desertions counted as fresh consideration, or if it was just part of their original duty.
The Judgment and its Reasoning
The court decided in favour of the claimant, Hartley. It was held that the captain’s promise to pay the extra money was legally binding and that Hartley was entitled to the £40. The judges found that there was valid consideration for this new promise.
The reasoning for the decision was that the circumstances of the voyage had changed so much that the original contract was effectively ended. Lord Campbell CJ stated that the desertion of so many crew members made it unreasonable and unsafe to require the remaining sailors to continue the voyage under their original agreement. The ship was unseaworthy with such a small crew. Because of this high level of danger, the sailors were no longer bound by their first contract. They were, in effect, free agents.
Therefore, when they agreed to sail the ship to Bombay in its dangerous state, they were doing something that went above and beyond their original duties. This new performance, undertaken in dangerous conditions they had not originally bargained for, was good consideration for the captain’s new promise of extra pay. Coleridge J added that the sailors could have legitimately abandoned the voyage without being in breach of contract. Their decision not to do so, and to take on the extra risk, was the fresh consideration needed to support the new contract.
Conclusion
In conclusion, *Hartley v Ponsonby* illustrates a key exception to the pre-existing duty rule found in *Stilk v Myrick*. While simply performing an existing contract is not good consideration, the court in *Hartley* found that where the performance involves work that is so different and more dangerous than what was originally agreed, the original contract can be seen as discharged. In these circumstances, an agreement to continue on is a new act that can be valid consideration for a new promise of extra payment. The case therefore provides a clear example of how a significant change in circumstances can alter the obligations between contracting parties and allow for a new bargain to be made.
References
- Hartley v Ponsonby (1857) 7 E&B 872
- Stilk v Myrick (1809) 2 Camp 317

