Improvised fuse

This fuse has been repaired with a piece of wire to byepass the cartridge fuse.

This may not be a hazard, so long as the wire that has been used is fuse wire of and of the right capacity - though there is no way of knowing.

This is not something that you would routinely spot during an inspection, and the simple fact that the wiring is so old as to have porcelain fuse holders may indicate that it is overdue for renewal, both an electrical hasard and a potentiail fire hazard