Harold Marcus entered into a contract with Corrigan’s Yacht Yard & Marine Sales, Inc., to trade in his 34-foot Silverton power boat toward a later model Mainship boat. He delivered his Silverton boat to the yacht yard at the time of the contract in November. The new boat was not to be delivered until the following April. The yacht yard sold the Silverton boat to William Heiselman soon after receiving it. When the yacht yard was unable to deliver the Mainship boat to Marcus in April, Marcus took back his Silverton boat. Who had title to the boat, Marcus or Heiselman? Explain. Heiselman v. Marcus, 488 N.Y.S.2d 571 (NY).