So Frank gave his warning, and saw that they obeyed. While they were in his employ he felt a certain degree of interest in these ragged fellows, and did not wish to be held responsible for any damage they might receive, if inclined to be reckless at times.
When he once more reached Andy's side the latter was looking through a pair of marine glasses they had fetched along, thinking they would prove especially valuable in scrutinizing the country over which they might be passing in the aeroplane.
"They're our friends, the revolutionists, I reckon," he announced. "I can see several who carry big swords that dangle around their heels. And the common soldiers, while they have little if any uniforms, and some of them no shoes, seem to all have guns in their hands. Here, look and tell me what that is on the little rise. I'm afraid our worst fears are going to come true."
"Well, you're right, Andy," replied the other, after he had clapped the binoculars to his eyes. "That's a cannon, all the same, and they're getting ready to shoot!"
"Oh! my! It makes a fellow's flesh just creep, to think of being banged away at with a great big cannon!" declared Andy.
"This one isn't so very big, I think. And now we're nearly opposite where the fire burns. They're going to make a move to show their hand. Drop down flat on the deck, Andy—quick with you!" and Frank, as he spoke, set the example himself.
Hardly had the two boys thus thrown themselves down than there was a heavy boom, accompanied by a brilliant flash of fire from the shore.
The revolutionists had fired upon the little steam yacht!