January 2nd.
2 injured.
Fig. 1.
Butterley, 26ft. 6in. long, and 9ft. diameter. The wagon-shaped top to the fire place was 8ft. 6in. long, and was attached to the bell-mouth of the internal tube, which then continued circular to the back of the boiler. The tube was 3ft. 6in. diameter. All the plates were about 7-16ths inch thick, and although the boiler was an old one, they were nowhere reduced in thickness by wear. The usual pressure of steam was 18 lbs., and a self-registering gauge showed that at the time of explosion it did not exceed 20 lbs.
The top of the fire grate on the right side rent longitudinally, and the upper part of the shell consisting of four rings of plates, and also the top of the fire place opened out and blew away to a considerable distance.
The front end also blew away. The bell-mouth of the tube was blown to the front, and the tube which remained in the back part of the shell collapsed upwards.
The cause of the explosion was most likely the intrinsic weakness of boilers of this shape, especially over the fire, where the top is only retained in its shape by numerous stays. The boiler had been very frequently repaired, at this the weakest place, and its strength had been thus so reduced as to make it unable to bear even a few pounds more than the ordinary working pressure.
The whistle was found to have been gagged by hemp, carefully inserted, so that there is ground for supposing there had been intentional unfair usage.
No.3. Blyth. ([Fig. 2.])