(o)A contracts to deliver 50 maunds of saltpetre to B on the first of January, at a certain price, B, afterwards, before the first of January, contracts to sell the saltpetre to C at a price higher than the market price of the first of January. A breaks his promise. In estimating the compensation payable by A to B, the market price of the first of January, and not the profit which would have arisen to B from the sale to C, is to be taken into account.
