At daybreak Wargrave and Tashi started on foot accompanied by a forest guard to put them on the track of the gang. This led up towards the Bhutan Frontier, which runs among the hills at an average elevation of six thousand feet above the sea. As the Assistant Political Officer anticipated, the party had headed for the portion of the border under the control of the _Amban's_ friend, the Penlop of Tuna. Enquiries among the inhabitants of the mountain villages resulted in several of them coming forward with the information that they had seen a small body of armed Chinese escorting a cloaked and shrouded figure on a mule and climbing up towards Bhutan. Two of the Government Secret Service agents among these Bhuttias had followed them cautiously to the frontier and seen them received there by a party of the Tuna Penlop's armed retainers. These men reported that the watch on all the passes into Bhutan was stricter than ever, and, as one of them phrased it, not even a rat could creep through unobserved. This discouraging intelligence was a further proof of _Amban's_ guilt. But Frank realised that it would not be sufficient to justify the Government of India claiming redress from the Republic of China; and, indeed, diplomatic procedure was much too slow to be of any use in the rescue of the girl. An appeal to the Maharajah of Bhutan would be equally fruitless; for his powerful vassal the Tuna Penlop was practically in rebellion against him and defied his authority. The sole hope of saving Muriel lay in Wargrave's prompt action. Yet try as the subaltern would, he and Tashi were unable at any point to pierce the cordon of guards along the frontier. Generally they got away unseen; but on one occasion they were discovered and had to flee back into British territory under a shower of arrows. Fortunately fire-arms are scarce in Bhutan; and the Tuna Penlop's soldiers possessed only bows. It was imperative that Wargrave and his follower should be circumspect in their movements, and by day they hid in caves or in the jungle clothing the slopes of the higher hills, to escape observation by Bhutanese spies. When they had exhausted the food that they had brought with them and failed to procure any more from their Secret Service agents in the villages, Tashi gathered bananas, dug up edible tubers like the _charpattia_ or _charlong_, and snared jungle-fowl and Monal pheasants. Having obtained a bow and a sheaf of arrows from a village he sometimes succeeded in killing a _gooral_, the active little wild goat found in the lower hills, the flesh of which is excellent.