338 Notice of the Great Explosion at Dover. 



seeing the prepai-ations for this grand event. The front of 

 the projection was about 100 yards wide ; this front was 

 pierced with a tunnel about six feet in height, and three in 

 breadth ; three shafts equidistant from each other and from 

 the entrances to the tunnel, were sunk to the depth of seven- 

 teen feet, and galleries were run, one from each shaft, paral- 

 lel with each other, and at right angles with the line of the 

 tunnel. These galleries varied in length, the longest having 

 been 26 feet, the shortest 12 feet, and, at their extremities, 

 chambers were excavated in a parallel direction with the tun- 

 nel. The following rude sketch may give a clearer idea of it. 





E 



] . The Tunnel. 2. The Shafts. 3. The Galleries. 4, The Chambers. 



In the chambers, the powder was deposited in three nearly 

 equal quantities ; it was done up in 50 lb. bags, and the pro- 

 portion in each chamber was contained in a wooden case 

 nearly as large as the chamber itself. Ignition was commu- 

 nicated by means of a voltaic battery. Conductors 1000 feet 

 in length were passed over the cliif, one to each chamber, and 

 the electric fluid was communicated in a shed built for the 

 purpose on the top of the cliff about fifty yards from the edge. 

 The explosion was conducted by Lieutenant Hutchinson, R. E., 

 who, you may recollect, was engaged under General Paisley, 

 in blowing up the wreck of the Royal George. Two o'clock 

 P.M. of this day, the tide being then at its lowest ebb, was 

 fixed on for the explosion to take place. The arrangements 

 were the best that could be made to preserve order, and as far 

 as possible prevent danger. A space was kept clear by a cor- 

 don of the artillery, and the following programme was issued : 



Signals, January 26. 1843. 



1st, Fifteen minutes before firing-, all the signal flags will be hoisted. 

 2d, Five minutes before firing, one gun will be fired, and all the flags 



will be hauled down. 

 3d, One minute before firing, two guns will be fired, and all the flags 



(except that on the point which is to be blasted) will be hoisted 



again. 



