Messrs. Chubb and Son’s safes are chiefly in two distinct qualities, the best being made as shown by the annexed engravings. The advantage of the diagonal bolts will be obvious; they fasten into a solid frame, which in its turn overlaps the body-plates, so that if it were possible to get a wedge past the rebate on the door, the moment the wedge was inserted the bolts would grip the sides and bind it tightly. The edges are joined by angle-iron, rivets and screws, and are rebated and dovetailed together.
Messrs. Chubb and Son have lately (1874) patented a new mode of construction, with the object of providing a stronger safe at a less cost than has hitherto been charged. The frame of the safe, on which the door hangs, is a solid T-iron, its outer edge overlapping the body-plates, and the flange receiving behind it the bolts. Though the inner lining has no screw or rivet, yet it is most securely fastened in the process of joining the other parts. In order to increase the fire-resisting properties of this new safe, besides the usual casing of fire-resisting material, a tube is introduced into the open space behind the T-iron, filled with a substance that will on the approach of fire cause steam to be projected into the interior of the safe. The engraving shows a section of one corner of this patent safe, and an elevation of it will be found facing page 36.