involved in the Construction of Artillery. 343 



the ghell, that they rarely resisted the shock of projection, and burst near the mouth 

 of the mortar, while the fuzes of others seemed to be bad. The very few, however, that 

 were fired successfully, produced effects so formidable, that the capitulation, which took 

 place before the breach was practicable, and within a kw hours from the explosion of the 

 first shell, was presumed to have been much precipitated by the persuasion of the Governor, 

 General Chassc, of the impossibility of maintaining the fortress under their continued fire. 



One of these shells fell within a few yards of the principal powder-magazine, but did 

 not explode ; had it fallen on the magazine, which was presumed bomb-proof, it was the 

 universal opinion of military engineers present, that it would have pierced the arch. The 

 magazine contained above 300,000 lbs. of powder: its explosion, therefore, as in the case 

 of the magazine accidentally blown up at St. Jean d'Acre, would have settled the contest 

 at a blow. 



This mortar, than which a more unwieldy, ill-constructed, and unmanageable instru- 

 ment could scarcely be conceived, was afterwards burst in experimenting with it on the 

 Heath of Braschaet. After having been fired with various charges, i'rom above 40 lbs. 

 downwards, — by which it was ascertained that less than half this quantity sent the shell as 

 far as the greater, — a charge of only 9 kilo. = 19'845 lbs. of powder, burst it. 



The unsatisfactory practice of these shells at Antwerp, as the author had opportunity 

 of knowing, arose from their defects of construction, from the extreme awkwardness of the 

 construction of the mortar and of its bed, and of the means employed for handling and 

 loading these heavy shells. Some experiments were made, in 1833, at Braschaet, which 

 proved that these shells, thrown to about a range of 3000 feet, at 45°, penetrated into the 

 solid earth of the Heath from 7 to 8 feet, and that the explosion of the bursting charge of 

 only 55 lbs. produced a crater of about 20 feet diameter. The splinters averaged from 

 twelve to fourteen, and were thrown an average distance of about 100 feet. 



This appears to be the largest scale upon which any attempt to throw shells, of a size 

 to be properly termed " Transferable Mines," had been made up to 1854. 



The weight of a 13-inch shell in flight varies from 180 lbs. up to 230 lbs. : the Antwerp 

 shell weighed as much as about five and a half such shells. 



We are now to compare the 13-inch with the proposed 36-inch shells. 



The weight of iron in the empty 36-inch shell may be assumed at 2481 lbs., and the 

 weight of bursting-powder, supposing the internal cavity full, at 480 lbs., — so that the total 

 weight of the shell in flight would be 2966 lbs., or above 1;^ tons. 



Assuming the angle and altitude of projection to be the same, and hence the velocity 

 on reaching the earth, neglecting resistance of the air, the penetrative effects of this shell, 

 as compared with a 13 -inch shell, will be directly as their respective weights, or as, say, 

 200:2966, which is nearly as 15 to 1 in favour of the large shell, supposing the surfaces 

 of impact the same. 



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