It was a great blow to all of them.
"Have you the sketch of the chart with you?"
The captain took it out of his pocket with a listless air.
"I am very much disappointed," he said. "If it is in that hollow I do not see how they could possibly be in condition to use the guns during the night. We could not see a trace of tracks to convey the ammunition to the guns at that place if any were there, and our shots fell all over the hollow back for a mile beyond the range indicated on the stone."
Alfred was intently examining the chart. "The commandant was puzzled at the figures 300, 200 and 60, which are in the circles below the arrows. Isn't it likely that they are there for some purpose?" asked Alfred.
"Unquestionably," replied the lieutenant. "Those figures may be the key to the whole reading."
"I'll tell you what I think," said Ralph, rising and walking about excitedly. "I have an idea about that 300. Do you know, Captain, how far it is from the depression where the arrow points to, to the top of the hill?"
"Not definitely; it might be about 450 or 500 feet; possibly more. But why do you ask?" remarked the captain.
"Well, here is the arrow, with the 5 at the head of it, on the right side of the line that runs east and west; and below the cross line and also on the right side is the number 300. Now, my idea is, that if the battery is not found at the place where the arrow points, it must be 300 meters to the right side of the direction given by the arrow," answered Ralph.