“you are sure of this, then?”

the voice of lieutenant timmons held a tone of deep interest as he gazed at the three blue-jackets standing bareheaded before him in his cabin. at ned’s request stanley and herc taylor had been included in the summons aft.

“absolutely, sir,” came stanley’s deep voice. “i’d know the butt of a crag-allen machine gun a block away, sir, and then the weight of those cases——”

“i think there is little doubt that you have stumbled upon the solution of the problem. the thing is to head them off. have you any suggestions, mr. stark?”

the officer turned to the young midshipman, the same whom ned had saved on the night the man was washed overboard.

“why, sir, stanley and his shipmates have acted so cleverly in this that it might be well to hear if they have anything to say,” he rejoined.

“begging your pardon, sir,” said stanley, thus encouraged, “but i think that it’s evident they mean to wait till dark and then take the guns down the coast somewhere.”

“by george! i believe you are right,” burst out lieutenant timmons. “most probably they are destined for the northern army of the revolutionists, which, i hear, is marching down the coast to join the main column. they gave the government troops an almighty licking, i understand, and it is doubtful if the latter can rally in time to join with the defending forces at boca del sierras.”

“but if they can, sir?” inquired the midshipman.

“in that case the government troops might be strong enough to defend the place. otherwise, that is, if a junction between the two bodies cannot be effected, the revolutionists bid fair to sweep[112] all before them. but go on, stanley. what were you about to suggest?”

“i thought, sir, if we could take the gas launch and make after them quiet like, we might find out where the arms were landed, or at least head ’em off.”

“a good plan, my man, but suppose they have several armed men on board? you know, in the delicate situation the united states occupies in this matter, we cannot afford to risk a fight.”

“no, sir,” broke in ned, “but supposing we borrowed the consul’s launch. that wouldn’t be identified with the beale, and we could head them off, perhaps, without any one being the wiser as to who it was.”

“the very thing,” heartily agreed lieutenant timmons, “only mind you, no adventures like those you had in cuba.”

“oh, no, sir,” laughed ned, flushing up.

“very well, then, that will do. you may go forward, and be subject to call. i will see to it that the launch is here—at about dusk, eh, stark?”

“yes, sir, i think that would be the best time,” rejoined the middy.

“well, you are to be in command of the expedition——”

“oh, sir!” exclaimed mr. stark, blushing under the honor. “thank you, sir,” he broke out.

“don’t thank me, stark. after all, it’s more hard work than honor, for it cannot be mentioned in the dispatches. i shall rely on you, however, to bring back the information we require as to the destination of the arms, and if you can do it without detection the arms themselves. will you require any more men than strong, taylor and stanley?”

“no, sir, the fewer the better, but we ought to have some one to handle the engine.”

“that’s right. i will get the engineer to detail a man to look after that.”

how that afternoon passed the boys could never tell. if ever hours were leaden-footed, those were. the consul’s launch came off during the afternoon, but immediately returned. during the time the diplomat had been on board,[114] however, the plan had been explained to him, and he had enthusiastically placed his craft at the disposal of the beale’s commander.

it grew toward dusk at last, however, and the boys ceased their impatient pacing of their cramped quarters. as for stanley, he was as cool as the proverbial cucumber. like several of the other men, he had borrowed a fish-line and was bobbing for red snappers most of the afternoon. quite a number of lines were cast overboard from the beale, and, though it cannot be said that much fish was caught, a wonderful amount of patience was displayed, so a good end was served after all.

the sun was disappearing behind the high mountains, beyond which a part of the insurgent forces were supposedly encamped, when ned, who was standing forward gazing at the sunset, gave an exclamation.

“there’s a picture!” he said.

tacking rapidly toward them across the glowing water was a small fishing craft. she moved[115] swiftly as the evening breeze filled her single leg-o’-mutton sail.

“she’s coming out to us,” cried herc suddenly.

indeed, it looked like it, and presently it was seen that herc was right. the little craft drew almost alongside the grim-looking destroyer before the figure at her helm hauled his sheet and put her about. as she shot away on the other tack there was a sudden splash from the beale’s side, and a man went floundering into the water.

“man overboard!” went up a cry, but it was instantly stilled, as it was seen that whoever it was in the water he was in no need of assistance. he could swim like a fish. a few strokes brought him once more to the side of the beale, and he was helped up. he stood laughing and shaking himself on the deck a minute later, and the boys, who were in the crowd that gathered about him, heard the word passed among the crew.

“it’s jim prentice, one of the engineer’s bunch.”

“how’d it happen, jim?” asked somebody.

“dunno. i was fishing and watching that[116] little boat when all of a sudden i slipped,” said the man readily.

“recognize that chap?” asked ned in a whisper, of herc.

“yes, it’s the fellow that gave us such a sizing up the other day.”

“that’s it. take a little stroll this way, i’ve something to tell you.”

ned seized the mystified herc’s arm and led him away from the group clustered about prentice, laughing and condoling with him.

“what do you suppose that fellow went overboard for?” asked ned mysteriously, as soon as they were out of earshot of the men.

“that’s a bright question,—because he couldn’t help it, i suppose.”

“not he. he went over for a purpose.”

“for a purpose?” echoed herc, looking sharply at ned.

“that’s what i said.”

“oh, for a swim, i suppose you mean—an unofficial swim.”

“no, something quite different from that.”[117] ned sunk his voice. “he went overboard to pick up a bit of paper that fellow in the boat threw out.”

had a bombshell exploded at herc’s feet, he could not have looked more astonished.

“your mind works quicker than mine, i guess, ned,” he said, “just as your eyesight is quicker. i didn’t see any bit of paper, but supposing there was?”

“well, it may mean nothing. the fellow may have a sweetheart ashore who chooses this means of sending him a message, and then again——”

“it might all have been an accident.”

“we may have a traitor on board,” resumed ned, not paying any attention to the interruption.

but whatever ned’s suspicions were, the call to supper prevented further voicing of them. in the midst of the noise and laughter and bandying of jokes that goes on about the jackies’ table, it was, of course, impossible to exchange any more conversation on the subject on their minds. soon after the meal, when darkness had[118] fallen, a messenger from the commander of the beale slipped unobtrusively up to ned.

“wanted aft, strong,” he said, with a significant look.

ned readily comprehended. the consulate launch must have come off while they were at supper. hastily he summoned his friends. without attracting any attention from the chatting, laughing tars, the trio slipped past the funnels and the conning tower, till they stood at the edge of the quarterdeck awning. here they stopped respectfully. naval etiquette did not allow them farther unless by command or permission. ned, however, with a sidewise glance, had noted that the dark outline of the consulate launch, a craft about thirty feet long, lay at the starboard gangway. the consul himself, a tall, dignified-looking man, with gray hair and goatee, sat in an easy chair talking to lieutenant timmons and his officers. the incandescents, which had been rigged under the awning, threw a sharp light on his features.

“ready, sir!” said ned, saluting, as did the others.

“all right, strong,” rejoined the commander of the beale. “your men are here, stark,” he said, as the middy came forward.

“you men will need arms,” said stark. diving below, he presently came up with three heavy caliber, service revolvers. he gave one to each of his followers.

a few minutes later they were in the launch and ready to start. it had been decided at the last moment that, instead of putting off directly from the beale when the gun-running launch hove in sight, it would be better to lie off one of the points at the entrance of the harbor, and then follow her up at a discreet distance. the boys were in ignorance of this, of course, but the man who crouched over the motor-boat’s engines evidently had his orders.

the midshipman, who sat up forward at the wheel, gave the bell handle two sharp jerks—the sign to get under way.

chug-chug!

the motor instantly took up its tune, and, with the muffler almost silencing the noises of the motor’s explosions, they glided into the velvety darkness illumined only by the bright tropical stars. the headland, in the shadow of which they were to wait, was soon reached, and then followed a long period of silence and watching.

at last, however, out of the blackness lying harborward, came a motor-boat’s sharp cough. it grew rapidly nearer and louder.

“here they come!” breathed stark, in a low, tense voice.