378. Mortgagees.

A mortgagee in possession may work open mines1 but he is not bound to make any greater expenditure on them than would be made by a prudent owner2. If the security is insufficient he may open and work new mines, but not otherwise3, and the burden of showing that the security is insufficient is on the mortgagee4. If a mortgagee who is not entitled to do so works mines he will be charged with the gross receipts and disallowed his expenses5, and he may be charged an occupation rent6; and persons working by his authority may be jointly liable