Now two shots went off at the same time.
"Those seem to be the balloon-guns," said the lieutenant.
Far below the air-ship hovered the clouds of two shrapnel shots.
"They're getting our air-ship ready over there," cried the captain; "that's the only sensible thing to do." He pointed to a spot far off where a large, yellow motor-balloon could be seen hanging in the air like a large bubble.
It went up in a slanting direction, and then, after describing several uncertain curves, steered straight for the enemy's balloon, which also began to rise at once.
Hundreds of thousands of eyes were following the course of those two little yellow dots up in the clear, early morning air, as the mountain edges began to be tipped with pink. The Japanese air-ship had reached a position a little to one side of that occupied by the 28th Regiment, when a tiny black speck was seen to leave it and to gain in size as it fell with increasing velocity. When it reached the ground a vivid red flame shot up. Tremendous clouds of smoke followed, mixed with dark objects, and the distant mountains resounded with loud peals of thunder which died away amid the angry rumblings in the gorges.
"That was a big bomb," said the captain, "and it seems to have done considerable mischief."
Now a little puff of white smoke issued from the American air-ship and ten seconds later an explosive body of some sort burst against a wall of rock.
"If they keep on like that they'll only hit our own men," said the lieutenant.
"The Jap is ascending," cried some one, and again all the field-glasses were directed towards the two ships.