A contracted with B to drill on the lattet's land, for $500 a gas well according to certain plans and specifications. B was to pay $250 when the work was half done and $250 upon completion. B left that state to attend to some business. A assigned thecontract to X. X, acting under the conhact, began to drill the well but became insolvent and abandoned the operation when the well was only one-third completed. Upon returning to the state and discovering what had happened, B asked A to complete the well, but A refused. B had the drilling of the well completed by another at a cost of $600. He then sued A to recover damages for breach of contract.

Will he recover? Explain.