The shrill yelp of a hurt dog had evoked Sherbrand’s exclamation. The sufferer’s plaint came from the Collingwood Avenue, on the other side of the fence. Thrice the excruciating sound ripped the ears, then died out in a sobbing whimper.... _That was for me!_ Bawne told himself, as von Herrnung went on: "Still, you are not pledged. There is no definite understanding. In the interests of the wealthy firm I am asked to represent—solely as a matter of courtesy, because they have been immensely civil to me in business,—you would not refuse me a test?" Sherbrand said, drawing off his left glove and showing blood oozing from under bluish-looking finger-nails: "I found it uncommonly parky to-day at 10,000 feet. There was a nor’-east breeze, a regular piercer. Found myself spitting blood rather badly, and to be candid, I was uncommonly grateful that the French Consul declined my offer, in case he was not satisfied, to do the thing again. The fact is, the operation, slight as it was, has weakened me a little. I wouldn’t care to repeat the performance without a good night’s rest to buck me up." Von Herrnung shrugged and agreed: "That it is cold at 10,000 I can credit easily. I have had the oil in my own gauges frozen at 7,000 in midsummer. _Da ist nicht zit strassen_. Hæmorrhage and dizziness are the chief enemies of the aviator. One’s stomach betrays one also, the cursed beast!—after a good hearty meal!" "I don’t give mine the chance!" Sherbrand returned, "but stave off the pangs of appetite with milk-tablets and meat-lozenges. Do all my flying on these and chocolate. Keep a little store of the things and a Thermos of hot coffee, in a _cache_ I’ve made for them, under the map-desk on the left of the instrument-frame, facing the pilot’s seat. If you will come over to the Bird I’ll show you, and explain the working of the gyroscopic hoverer." He added, looking squarely at von Herrnung: "Of course the cutting of the double screw is the chief thing about the invention. I’ve registered every way I know and got a trade-mark. They tell me at the Patent Office that my international rights are secure!" "They should be, if you have those precautions taken. It does not do to trust," said von Herrnung, "too much! The monkey proverb is law for most men." He shrugged. "It comes, by the way, from Namaland in German South-West Africa. ’_Nuts in your pouch are nuts in mine!_’" The freemasonry of their calling had established a degree of friendliness between them. They were laughing over the monkey’s philosophy as they went over together to the Bird. The small boy who had been idly sprawling on the hot turf near them, with his tilted hat shielding his face from the westering sun-rays, got up and trotted after them like a collie pup.