A REMARKABLE EXPLOSIOX. 811 



seven miles distant from the center of the city, had. exploded, being 

 struck by lightning. It contained at the time some fifty tons of or- 

 dinary gunpowder and fifteen tons of dynamite. The brick walls of 

 the building were pulverized and scattered over a wide area ; the 

 limestone foundation was torn up, and a large part of the material 

 broken into small pieces, the most of it carried through the air from 

 forty to eighty rods ; and a hole was torn in the ground, there mainly 

 tough clay, about one hundred and fifty feet long, forty feet wide, and 

 from ten to twenty feet deep. All the buildings in the immediate 

 vicinity we're demolished, while those which stood within reach of the 

 flying stones were more or less riddled. The loss of life was very 

 small, considering the extent of the damage, only one person having 

 been killed outright, although several others were severely injured, of 

 whom some have since died. 



Such are the primary facts connected with the explosion itself. An 

 examination of the ground in the vicinity, and of many of the build- 

 ings ruined near by, together with others at considerable distance more 

 or less injured, has developed certain minor facts that bear upon the 

 general subject of explosions. Especially do they seem to show that 

 such explosions may produce an earth-wave which may do damage at 

 great distances, the undulation of the ground displacing objects, crack- 

 ing walls, and shattering glass much like an earthquake in miniature. 

 Sometimes this may possibly prove the source of the principal destruc- 

 tion. 



Looking directly at the destruction itself, the results of the ex- 

 plosion appeared as follows : The buildings nearest the wrecked maga- 

 zine were all crushed together, and, so far as could be determined from 

 the ruins themselves, were pushed away bodily from the demolished 

 building for a short distance, not more than one or two feet. This 

 shows that the explosives instantly produced a very large volume of 

 gas, which forced itself against the surrounding air, and condensed it 

 very quickly, until it gave way in the direction of the least resistance, 

 which would necessarily be upward. This condition was confined to 

 a small circle, for, while such a condensation would produce a wave 

 of air, the mass bodily displaced must be confined within compara- 

 tively narrow limits. Displacement would not appear beyond. Fortu- 

 nately, at Brighton, no other magazine stood within this area, so that 

 the dynamite in the others was unaffected by the shock, while the rain 

 prevented the fire from spreading by means of dry powder. Outside 

 of this area there was a narrow ring or circular strip of ground with 

 a radius of not far from fifteen rods where comparatively little injury 

 was done. One or two magazines stood in this region, and they es- 

 caped almost without injury, only being slightly battered by flying 

 stones. Here the air was not moved as a mass either way. The 

 changes of density to which it was subjected were of the nature of 

 molecular movements rather than motion of any great mass of air. 



