The licensee of an agricultural allotment under "The Land Act 1884" (No. 812) has by sec. 120 all the rights as against persons trespassing with any cattle, sheep, goats, or swine, but not against other mere trespassers, which at law belong to the owner in possession of any land as against trespassers thereon, except the right of impounding such cattle, sheep, goats, or swine, and has the last-mentioned right when and so soon as the allotment, or such part as shall be trespassed upon, has been enclosed with a "substantial fence," but not before.