182 TliAXSACTIONS OF THE AMERICAN INSTITUTE, 



tons, and was a mnd-tight piston, fitting the box tightly. The great 



ancient rival of the " Swamp Angel" was the " Mons. Meg," now at 



Edinbiirg Castle, It is thirteen and one-half feet long and twentj 



inches bore, with a powder chamber of nine and three-qnarter inches 



diameter, and the charge was a " peck of powder." The balls used 



were of stone, eighteen and one-half inches in diameter. It was used 



at the siege of Dunbarton in 1489, and was injured in firing a salute 



in 1682. There used to be a quaint inscription upon it, about in 



these words : 



" Lpad me well, and sponge me clean ; 

 And I'll drop you a shot at Calais Green, 



sixteen miles. There was some poetic license used by this ancient 

 rhjmster, for one of our distinguished engineer oflicers informs me 

 that with the most liberal allowances, in his calculations and with the 

 advantage of ricochet on water, this gun could not possibly have had 

 a range exceeding one and a half miles.* 



The capture of Fort Pulaski, near Savannah, aftbrds a good illus- 

 tration of the unerring certaint}'' of the calculations of the efiect of 

 ordnance by modern military engineers. The breaching batteries had 

 to be placed at a mile from the fort. The engineer (who is also a 

 member of our civil society) prepared his plans before leaving Wash- 

 ington, complete in every particular. I cannot refi-ain from using 

 the general's own words, although stated at a social meeting, the/', 

 have so thoroughly the ring of the true metal of the engineer, who, 

 with science, experience, and judgment, knows the result of his opera- 

 tions before he begins them. He said: "The capture of that work' 

 had been calculated and worked out on paper, with an almost abso- 

 lute certainty, of the preestimated results, and I had almost as much 

 confidence in my ability to breach the walls, as if I had gone to work 

 on them with masons, hammers and chisels." Whitelaw Reid, in 

 liis " Ohio in the War," says : " On the evening of April 9, 1862, 

 Gen. Gillmore issued his order for the bombardment. It was remark- 

 able for the precision with which ev|iy detail was given. Tlie direc- 

 tions for the breaching batteries will illustrate." [Here follows Gen. 

 Gillmore's order.] Mr. Eeid continues : " These instructions, with 

 few exception, were adhered to throughout. For their striking illus- 

 tration of the unerring as well as preestimated results of applied 

 science, engineers and artillerists will hold them not among the least 



* It should not weaken confidence- in these calculations when I add that they were made by the- 

 gallant officer who bad the dircctioB and firing of " Mons Meg'a" great rival, the " Swamp Angel.'*" 



