“You take a whole lot for granted,” bantered the captain, with a wink at Josh.

The young aviators had their way, for it was just the way that suited Captain Johnson.

Hovering over the warships engaged in the bombardment, Johnson and Freeman, as observers and signal scouts, by the flag code kept the range finders on the gun decks apprised of the shots that told, as well as those that were ineffective.

They also showed the sign of warning against the approach of several Turkish torpedo boats, which were quickly turned by the hot reception measures taken by the warship gunners.

Several times in the lower strata the circling biplanes were jarred and dangerously shaken by the concussion of the tremendous gun-play.

On these occasions a rapid upshoot restored the fluttering flying machines again to even keel.

For three or four hours the four daring aviators were aloft and running the whole gamut of air perils attendant upon signal service over cross-fire of big guns.

With the retirement of the cruisers came relief, and when Billy and Henri got the word to backtrack they sent the machines along like two streaks of lightning.

“That ought to hold you a day or two,” grimly observed Captain Johnson, stamping the kinks out of his legs on the landing place, and addressing his young friends, who were also working off the strain by a vigorous arm-rubbing.

“Another job in the morning,” stated Billy, “and in a house on wings. Come around and see us start, captain, you and Josh.”