right nice o’ you to talk that way, brother,” Perk hastened to assert, beaming with pride and making out as if tempted to begin scratching again when Jack reaching around, gently steered his clutching fingers away from the itching locality, at which Perk heaved a relieved sigh and nodded his thanks.

“The sky has lost most of that glorious color,” mentioned the head pilot, “and before long now we can be hopping-off. Our first job will be to swing down the coast and learn if there seems to be anything going on among the southern islands in this beastly mangrove section where a man could easy enough lose himself for keeps among the countless water passages and inlets. See here, what’s the matter with you, staring that way, Perk?”

“Wouldn’t that jar you now,” snapped the other, “that Robin ship is headin’ back this way; or else some other crate that looks like its twin!”

CHAPTER II
THE CURTISS-ROBIN PLANE

Jack, a bit startled by his companion’s sudden exclamation, took a good look and hastened to remark:

“Reckon now you hit the nail on the head that time, Perk and it’s heading this way in the bargain. Why d’ye suppose we didn’t see the crate before?”

“Huh! I kinder guess now,” Perk went on to say, “she bust out o’ that little fog cloud right to the south–a’swoopin’ up the coast, you notice, partner, don’t you?”

“Sure is,” assented Jack, as though that small circumstance assumed some importance in his eyes, as well as those of his comrade.

“Ginger pop! but mebee I ain’t glad we didn’t show any hurry to kick off this camouflage green stuff, thinkin’ it’d served its purpose okay and could be knocked into the discard. See how they keep dodging’ in an’ out like they might be scourin’ every foot o’ shore line, little bays back o’ these mangrove islands an’ all. Strikes me they’re a’searchin’ for somethin’, Jack, which might be the pair o’ us, eh, what?”

“Right you are!” snapped Jack, without hesitating a second.

“Which, I take it, would mean there might a’been some sort o’ little leak up at Headquarters, hang the luck, when we figured we’d got the gang buffaloed right smart. Don’t think they c’n lamp us lyin’ here, do you, Boss?”

“Small chance of that, boy, if only we lie low, and make no move apt to attract their attention,” Perk was told in a confident tone that effectually calmed his rising alarm.

He hastened to settle down in a position where he could thrust his glasses between interstices in the green covering of the fusilage and wings so as to keep close tabs on the advancing plane without making any particular movement of arms or body.

“How?” asked Jack, a few seconds later, when he fancied his mate must have made up his mind as to the identity of the flying ship.

“Curtiss-Robin crate, that’s right, Jack an’ the same we saw before,” replied the observer, excitedly. “Hey! guess now they got a glass up there too. I sure saw the sun shinin’ on somethin’ bright, ’cause the old boy’s still on deck to chaps that high up.”

“I’ve discounted that fact long ago, Perk; men engaged in the desperate game they’re playing night after night would need such a useful instrument, so’s to keep a sharp lookout for Coast Guard boats or bunches of revenue men lying in ambush close to the place they expected to land a wet cargo, or a couple of high-pay Chinks, it might be.”

“Then you got an idea they must have a spy up in Washington–a sneaker who c’n find out what’s bein’ hatched up so’s to cook their goose an’ that he manages to get warnin’ down here to the workin’ crews so’s to put ’em on their guard–is that it, partner?”

“Looks that way–that’s all I can say, Perk. Now lie low and don’t do any talking, though with their crate kicking up all that row I reckon there’d be small chance of their hearing us even if we shouted.”

Perk was chuckling to himself at a great rate and could not keep from taking advantage of the invitation Jack had really extended to say:

“Yeah! an’ I kinder guess now we got one thing they ain’t, which is a silencer on our engine that’ll keep it muzzled, even if it does knock off a bit o’ our speed when we happen to use it. Luckiest thing ever you managed to get the Big Boss to send us such a bully contrivance that seems to work jest great. Listen to the racket they’re kickin’ up right now–enough to tell any chump ten miles off a crate’s headin’ his way. Jerusalem crickets! but ain’t I glad we’re fixed as we are.”

The ship far up in the heavens was almost directly over them by this time and Perk relapsed into silence, being vastly interested in watching it passing over.

Possibly he had his eyes glued on the figures–there were two occupants in the Robin’s cabin he could easily see–leaning over and doubtless closely scrutinizing the intricacies of the ragged shoreline below, hoping to make important discoveries.

If the leading figure, piloting the craft, was actually Oscar Gleeb, onetime noted Hun ace over in the Argonne, it might be Perk, with his past war history rising up to thrill him afresh, may have found himself half expecting to hear a terrific explosion close by on the shore as the German flier let drop some sort of bomb, with the idea of striking their concealed bus which his keen eyes might have detected despite their wonderful camouflage.

But nothing like that came to pass and the cruising ship kept moving in a northerly direction, growing less distinct as miles were being covered at the fast clip it swept along.

“Cripes! that was worth somthin’ to glimpse, bet your sweet life, partner,” Perk finally observed as he ventured to make a little movement, feeling dreadfully cramped and the danger of discovery growing momentarily less as the first shades of coming evening began to gather around the secluded cove. “Jest as like as not they started away down toward the tip o’ the mainland, an’ hev been examinin’ every mile o’ the coast, bent on doin’ a clean job while they’re at it. An’ if they meet up with no luck mebbe now they’ll make up their minds it was only a false alarm, and let her go at that.”

Presently they could no longer glimpse the faintest sign of the scout plane–when last seen it was still heading up the coast as though making for some destination where action awaited the members of its daring crew.

“The passing of that crate settles one thing, anyway,” observed Jack presently.

“As what, partner?” queried Perk, who had already begun to denude the anchored amphibian of its covering, as though it was settled they need no longer fear being spied upon from above.

“We needn’t bother striking into the south when starting out to look for suspicious lights, such as would tell of business being put through–those boys are right now heading for their rendezvous and it’s our game to chase after them, as soon as nightfall makes it safe to get a move on.”

“That suits me fine, Jack old hoss. I’m right sick o’ keepin’ our nose stuck so close to the ground–me for the high places where I c’n get my lungs filled with clean air–this swamp