Explanation:

Mortgage by deposit of title-deeds.

 According to Section 58(f) Mortgage by deposit of title-deeds.—Where a person in any of the following towns, namely, the towns of Calcutta, Madras and Bombay, and in any other town which the State Government concerned may, by notification in the Official Gazette, specify in this behalf, delivers to a creditor or his agent documents of title to immoveable property, with intent to create a security thereon, the transaction is called a mortgage by deposit of title-deeds.