He then crawled up on the mound two or three yards below the end of the bury, and with his own hands stretched a larger net right across the top of the bank, so that if a rabbit did escape he would run into this.

To be still more sure he stretched another similar net across the whole width of the mound at the other end of the bury.
He then undid the mouth of the ferret-bag, holding it between his knees--the ferrets immediately attempted to struggle out: he selected two and then tied it up again.

With both these in his own hands, for he would trust nothing to another, he slipped quietly back to Orion's side, and so soon as he saw I was standing well back placed them in different holes.
Almost the next instant one came out my side disarranging a net.

I got into the ditch, hastily reset the net, and put the ferret to an adjacent hole, lifting up the corner of the net there for it to creep in.

Unlike the weasel, a ferret once outside a hole seems at a loss, and wanders slowly about, till chance brings him to a second.