178. Mortgage of incorporeal hereditaments.

Incorporeal hereditaments, such as manors, commons, rentcharges and other property of a like nature existing in gross and apart from the ownership of corporeal property, may be the subject of a mortgage; but only such incorporeal hereditaments as can exist at law1 can be the subject of a legal mortgage. The mortgage is in the same form, so far as applicable, as in the case of other hereditaments2, and if it is a legal mortgage it must be by deed3. The only profitable parts of a manor which may now exist are mining rights, franchises and sporting rights preserved