It is the substance of the transaction as contained in the instrument that determines the stamp duty. Elucidate.

Courts have held the principle of substance of the transaction, over the form, in the matter of deciding the nature of the instrument. The substance of the transaction contained in the document may not necessarily embody the description given at the head thereof. It is the substance of the transaction as contained in the instrument and not the form of the instrument, that determines the stamp duty, though the duty is leviable on the instrument and not on the transaction. In determining whether a document comes within the description of a document upon which a stamp is required by the Indian Stamp Act, 1899 one has to look at the entire document to find out whether it falls within the description. Where a single instrument contains several purposes, the instrument as a whole should be read to find out its dominant purpose. To determine whether a document is sufficiently stamped the Court must look at the document itself, as it stands.