1879.] on the ' Thunderer ' Gun Explosion. 239 



rest. The iuformatiou that tlio charge is homo, is afforded audibly, 

 by the concussion arising from the striking of the cartridge against 

 the cud of the bore, and the position of the rammer is indicated 

 visibly by a hand made to revolve on a dial by means of a lino 

 attached to the rammer head. 



When the gun is loaded, those in charge of tliat operation give 

 also a visible signal by a tell-tale, to the crew within the turret : 

 " Left gun ready," or "right gun ready," as the case may be. The gun 

 is then raised from the depressed position, is run out by the hydraulic 

 apparatus through the i)ort, and is adjusted as to level for firing, the 

 turret is unlocked and is revolved until the gun bears upon the object, 

 and then the gun is fired. This firing may be done either electrically 

 or by hand : in either case a tube is inserted into the vent ; this tubo 

 contains powder closely rammed, and there is a composition in its 

 head which in tho case of electrical firing is ignited by an electric 

 spark conveyed through a wire couijled up to another small wire 

 which you see projecting from the head of the tube. 



Electrical firing is used to give a simultaneous discharge from all 

 the guns, so as to concentrate their fire upon the object aimed at. 

 When electrical firing is employed, the whole ship becomes the 

 gun carriage and the firing is done not by the officers in the 

 turret, but from the " conning " tower ; to a key in which the wires are 

 connected. When the ofScer in the conning tower sees by the aid of 

 an instrument, the " Director," which he has there, that the guns arc 

 bearing on the object, he depresses the key, and thus if no misfire 

 takes place delivers a concentrated broadside. In the other mode of 

 firing the guns, the composition in the head of the tube is ignited by 

 a friction arrangement ; this is put into operation by pulling a lanyard, 

 and there is a contrivance by which, if desired, both the lanyards in 

 one turret can be pulled simultaneously. 



Having now described to you the construction of the gun, the 

 mode of loading, and other matters necessary to be described in order 

 to place you in a position to appreciate what occurred, I will briefly 

 narrate the circumstances attendant on the working of the guns on the 

 2nd of January last. 



The two guns of the fore turret and the two in the after turret 

 were each loaded with a battering charge of 110 lbs. of j^ebble 

 powder, and with a Palliser shell, emj^ty, the two guns of the foro 

 turret having in addition disc wads. In the after turret the naval 

 wedge wad was not used, as the guns were loaded in a horizontal 

 position, and the sea being smooth there was no fear of the projectile 

 being shifted by the rolling of the vessel. 



All four guns were primed with electric tubes, and were to bo 

 discharged as an electric broadside, the discharge being effected, as 

 already stated, by the depressing of the key in the conning tower. On 

 the depression of the key on this occasion, beyond all question there 

 was a misfire as regards one of the two guns of the after turret. 



