Reservation of right of disposal preserves seller's property in goods until contractual conditions are met despite delivery. A seller may reserve the right of disposal over specific goods by contract or appropriation so that property in the goods does not pass to the buyer until the seller's prescribed conditions are fulfilled, despite delivery. Goods consigned to a railway with documents making them deliverable to the seller's order prima facie evidence such a reservation; where a bill of exchange is secured by transmission of the bill of lading or railway receipt, wrongful retention of those documents by the buyer prevents passage of property.