“The Black Emperor got to the gate long before the rain stopped last night,” he said, staring at the ground. “See, his tracks are almost but not quite wiped out by the rain. He came home following the road. You’d better get your breakfast, lad, and I’ll put every available man up on a horse. You’ll have to organize a muster of the paddock. Pity the ’drome’stoo boggy to let you get the plane aloft. I’d better ring up Blake. We might want his tracker out here.”

Sergeant Blake was breakfasting with his wife when the telephone shrilled a summons to the office, one of the two front rooms of the station building which fronted the only street in Opal Town. The senior police-officer controlling a district almost as large as England and Wales was dapper but tough. His weathered face emphasized the grey of his well-brushed hair and carefully trimmed short grey moustache. His wife, a large woman his own age-forty-six-made no remark on this early call, and silently placed her husband’s half-eaten breakfast chops into the open oven.

Correctly dressed in uniform, the Sergeant thudded along the passage to the telephone. From beyond miles of mulga forest and open plain a deep, booming voice spoke.

“That you, Blake? Lacy here. Sorry to ring you up so early. I fear that Jeff Anderson has met with an accident somewhere out in our Green Swamp Paddock. May want your help later.”

“What’s happened?” asked Blake, his voice metallic.

“I sent Anderson into Green Swamp Paddock yesterday morning to ride the fences. He hadn’t come home last night, and we thought it likely enough that he had camped for the night at the hut out at the swamp, seeing that it was raining and that we always keep a few rations at the hut.