over outlying districts. The fleet had evidently separated on nearing the city, thus minimizing the risk of being brought down by volleys or shrapnel, or the efforts of airplane defenders who were already rising to give battle to the German monsters.
"There, they dropped something, for I could see what looked like a spark falling!" exclaimed Tom suddenly.
"That was a fire bomb," said a man standing near, who probably had passed through number of similar attacks, and was well posted. "It is filled with combustible fluid, and on bursting sets fire to everything around."
Hardly had he spoken when they heard a terrific report. At the same instant there was a vivid flash, as of fire. The boys were reminded of lightning on a black night; but in this case the glare stayed, as though the fire had accomplished the work intended.
Quickly following there came another frightful smash.
"That was a regular bomb!" cried the man close to Tom. "Chances are it's done considerable damage, for it must have dropped in one of the congested districts."
"But there are no fortifications inside London, are there?" asked Jack, horrified at the thought of death and destruction being scat-
