"How far along the passage is the grating?" Mackenzie asked in a whisper.
"About half-way, sahib."
"And on which side?"
"Side nearest us, to be sure, sahib."
"Wait here for me, and hold this."
He placed in Hamid's hands the end of a coil of string, climbed over the embankment, and made his way with stealthy speed towards the middle point of the passage wall, as nearly as he could judge it, paying out the string as he went. On reaching the wall, he turned swiftly back, coiling the string round his finger. When he regained Hamid's side, he knew that the distance between the wall and this point of the embankment was a little more than sixty yards. The chimney which his friends were cutting would reach the surface somewhere on the circumference of a circle of which the middle of the wall was the centre, and which would come within about ten yards of his present position. He followed that imaginary line with his eye. It passed close to one of the summer-houses, ran across a bed of plants, then over the grass on which he had walked, touched the embankment some yards to the right, owing to the oblique course of this, and finally reached a point near the door of the cook's lean-to. To gauge the position of the chimney more precisely was impossible, because, though he knew that it was on the near side of the passage, he knew no more than that it was fifty yards from the grating.
Making a mental note of the course of the circumference on which lay the locus of the hole sometime to be pierced, he considered for a few moments whether to steal towards the door of the pagoda, and try to discover whether it was guarded. But by this time he was shivering with cold. His reconnaissance had not been unfruitful, and he decided to return at once to his hut. He parted from Hamid at the culvert, handed him the blanket, again entered his cold bath, and picking up his clothes, ran lightly over the ground to his lodging. Only on those two night expeditions had he taken off his clothes since his departure from the village in the forest.
Next morning Hamid handed him a note which he had drawn up in the bone. It was the longest he had yet received: Forrester had grown bolder, more reckless, perhaps, with the lapse of time. It read: "Always light below. Can't tell when it becomes dark outside. Give us a sign."
"Things are moving," he thought. "They are afraid of cutting through in the daylight. How in the world can I give them a sign? Hamid lets down the bone at all hours. Ah, well, I must think it out."
CHAPTER XVII