Frightful Exptaion at the Arsenal.LARGE NUMBER OF THE FEMALE EMPLOYEES KILLED OR FRIGHT FULLY WOUNDED. -EIGHTEEN dead bodies taken out ofTI1E RUINS ALREADY.At ten minutes of twelve o’clock to-day a terrible catastrophe occurred at the Arsenal, which has cast a gloom .over the whole com* mnnitt* and rendered sad many a heart that was buoyant a few moments previous.While one hundred and eight girls Were at work in the main laboratory making cartridges for small arms, a quantity of fire works, which had been placed off the outside of the build ing, became ignited, and a piece of fuse flying into one of the rooms, in which was seated about twenty-nine young women, set the cartridges on lire, and caused an instantaneous explosion.The building in which the explosion took place is a one-story brick, divided off into four rooms, and runs east and westThose girls who were employed In the east rooms of the laboratory, mostly escaped by jumping from the windows and running through the doors pell meli; but those iu the room fronting on the east, did not lare so well, and It is feared that nearly all of them were killed bv the exnlosion or hnrnt to death.