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Daniel borrowed money from Carl. As security, Daniel executed a contract of pledge over his vessels which, however, were not actually delivered to Carl but remained in Daniel's possession who shall hold said property subject to the order of the pledgee. Daniel defaulted. Pursuant to the terms of the pledge, Carl took possession of the vessels and sold the same. Daniel contended that the pledge was not effective because there was only constructive and not actual delivery of the vessels to Carl. Is the contention of Daniel tenable? Explain your