46 Mr. E. Jekyll on Siege Operations. [Feb. 16, 



character of the attack is changed ; and as the besieger proceeds 

 with the trenches on the surfjice of tiie ground he has to secure 

 himself from below. Twelve days are added to the duration of the 

 siege, if the fortress is ably protected by a well-arranged plan of 

 defensive mines, in the more advanced galleries of which he can 

 listen for the stroke of the miner's pick, and by means of a pea, placed 

 upon a tightly-braced drum, subterraneous workmen can be dis- 

 covered at the distance of from 60 to 90 feet in ordinary soil, 

 hence such listening galleries, as they are termed, are built distant 

 from each other 120 feet. When the advancing miner is discovered 

 by the defenders of the fortress, a mine is hastily prepared, and the 

 assailant blown to destruction. Occasionally a long iron probe is 

 used, to ascertain the nature of the ground in front, or the position 

 of the works of the besieged ; and if such instrument reaches into 

 the defensive excavations it is followed on withdrawal by a charged 

 rifle or musquetoon, and a shot is fired upon the assailant, or com- 

 bustibles generating noxious gases are thrust into the aperture. 



The subject of mining is far too extensive a one to be embraced 

 in so limited a description, but the globes of compression of the 

 besiegers, or surcharged mines, finally overthrow the network of 

 galleries with which the fortress is surrounded ; and the craters 

 or hollows formed by their explosion, afford cover and the more 

 ready means of pushing forward the saps and trenches, and the 

 fortress is compelled to surrender. In describing the various en- 

 gines of war, and the recent improvements made in them, Mr. 

 Jekyll alluded to the making of cannon shot of a conoidal form, 

 and the recently discovered danger of exposing live shells to the 

 enemies' fire, both in batteries and on ship-board ; — shells struck by 

 shot instantly explode, the blow raising the temperature of the 

 stricken part far beyond the heat at which gunpowder inflames. 

 Some of our first-rate men of war have their lower batteries of 

 shell guns only ; and as each gun has two shells in boxes placed 

 over each piece of ordnance, 64 mines are thus prepared for the 

 destruction of the vessel, liable, during action, to add their ravages 

 to those occasioned by the fire of the foe. 



In conclusion, comparison was drawn between the attack upon 

 an ordinary pentagon, and the siege now in progress in the Crimea. 

 In the former the prize was sure of being gained, inasmuch as the 

 place was always previously invested, contained a garrison of but 

 5000 men, and was defended by 150 pieces of artillery, a portion only 

 of which could be used in the defence of the single side attacked, a 

 length seldom exceeding 320 yards ; the besiegers, with an over- 

 whelming force of men and ordnance, having established themselves 

 behind safe approaches, batteries, and a parallel or envelope embra- 

 cing the fortress of a length of 2000 yards, finally ruined the 

 defences of the fortress. At Sevastopol investment had been im- 

 practicable ; the parallel of the allies, broken by the nature of the 

 ground, was of no greater extent than 2300 yards, and the Rus- 



