Tracing trust property: beneficiary can claim substituted assets or an equitable charge when trustee transfers or converts trust assets. Where trust-property has passed to a third person or been converted, the beneficiary may require admission or seek a declaration that the property is comprised in the trust; if the trustee's disposition yields traceable proceeds or substituted assets in the hands of the trustee, representative or transferee, the beneficiary's rights in those proceeds or assets are, as nearly as may be, the same as his rights in the original trust-property, including rights to the substituted asset or an equitable charge corresponding to misapplied trust-money.