Tracing is the process of identifying a new asset as the substitute for the original. In Taylor v Plumer (1815) 3 M. & S. 562, a client gave money to his stockbroker, Walsh, to invest. Walsh purchased bullion and investments with the money and was caught making off to America with them. It was held that the client could claim the bullion and investments. On Walsh’s bankruptcy, his assignees in bankruptcy sought to recover them from the defendant client. They failed. Lord Ellenborough held:

It makes no difference in reason or law into what other form, different from the original, the change may have been made, whether it be into that of promissory notes for the security of the money which was produced by the sale of the goods or the principal as in Scott v Surman (1742) or into other merchandise, as in Whitecomb v Jacob (1710) for the product of or substitute for the original thing still follows the nature of the thing itself, as long as it can be ascertained to be such...