While the beach lasted, Biggles found the going easy, but he advanced cautiously, keeping a watchful eye on the bushes that skirted the foot of the cliff. Presently large boulders and rocks that had fallen from above obstructed his path, and progress became slower. From time to time he climbed up to the top of these and examined the surface of the water critically; he was soon glad that he had taken the precaution, for in many places he could see great masses of dark rock just below the surface which would have crushed the bottom of the Condor like an eggshell had the amphibian come in contact with them when taking off.
CondorThe position of these he tried to memorise, and, to make doubly sure, he marked them down on a rough sketch-map. From time to time he could still see the machine, wi
