apapiu/simple_text_files · Datasets at Hugging Face

"Either that or they have changed their course, and are now leaving us dead ahead."

This was a blow to the poor boy, whose hopes, brought about by the apparently checked motion of the ship, were now dashed to the ground, when the Professor continued: "They are sailing away, I am sorry to say."

He left the observation stakes. Poor Harry was still signaling frantically. The Professor told Harry that further effort in that direction would be useless, and he slowly and sadly came down the hill.

They looked at each other most sorrowfully, and the boys could scarcely restrain their tears, while the Professor carefully avoided their gaze, or seemed not to notice their grief.

"It is one satisfaction to know," said Harry, as he dolefully looked across the broad sea, "that vessels do come this way, and that it is not out of the world entirely."

George quickly recovered. "Why not make a big signal flag for Observation Hill?" This was seconded by the Professor.

"And while we are about it why not make a good old American flag?" was Harry's comment.

The cave had been forgotten in this incident. When their wondering and questionings had ceased, the descent was made around the point, and the entrance soon reached.

The two lamps were now lighted, and the explorations began.

"I think it is advisable," was the Professor's first observation, "that we go in a hundred feet or so, and then mount one of our lamps in a conspicuous place. We can then proceed with the other as far as the water, and if any accident happens it will not cause trouble to both of the lights. We can always have one of them to fall back on."

When they had gone the distance determined on, a secure ledge was selected, and Harry placed the light so it would cast its beams along the cave.

"Be careful now, we are near the water."

The Professor had now the other light, and the boys led the way, so the beams from the light shone past ahead of them. They went beyond the point where the water had been found previously, but there was no sign of it. The course of the cave now changed to the right, and the floor of the cave went downwardly at a slight descent.

The Professor suddenly restrained the boys. "Wait a moment; the light behind us should be brought forward to this point."

George went back and brought it up, and after some delay a place for it was found. The two lights now plainly showed a sudden enlargement in the area of the cave, and above them hung what appeared to be huge icicles, giving the interior a weird appearance. Still no water was in sight.

"The white substances we see all around us indicate that above us the rocks are limestone, and water, in coming through, has acted on the stone so as to form carbonate of lime, or chalk."

The single lamp was now sufficient to light up the interior, which looked like a domed iceberg, with all sorts of fantastic figures standing out in bold relief, which were contrasted by the many dark recesses irregularly scattered about everywhere.

"I see an opening beyond," was Harry's remark, in a suppressed tone.

The contracted opening was to the left, and he quickly made his way over the uneven floor to that point. "The water is beyond, and I hear something there."

George quietly moved forward. The light from the Professor's lamp glistened on the surface, and rippling waves were easily distinguished.

"What has become of the light we had on the perch?" was the Professor's startling inquiry.

The boys looked back. It was not there. Probably it had gone out.

"We must not go on until we have relighted it," was the Professor's caution.

George went back. The light from the Professor's lamp still threw its rays back to the ledge, which was not more than a hundred feet from their present location. "I can't find it. It is not here, and I know I put it on this ledge. Here is the piece of lime I put up against it."

Too startled for words, Harry drew back from the opening. Without further conversation he and the Professor retraced their steps toward George, who was now frantically searching every crevice.

"That is too bad. Are you sure this is the place?"

"I am positive of it."

The boys looked at the Professor. He knew they mentally asked whether they should proceed with the single light. "I think it would be unwise to go farther with one light only. If we can do no better we can make a half dozen lights, and light up the whole cave. I am just as much interested in it now as you are."

They were about six hundred feet from the mouth of the cave, as nearly as could be estimated.

"Before we return we might as well chart the cave, so we shall have some idea of its crooks and turns. Have we anything to measure with? If not, have you a cord, so we can get some idea of distances?"

George held out one of the spears, which was about five feet long.

"That will answer," said the Professor. "Let us call this five feet long for the present. The first thing we must do is to establish a base line. But what shall we do for something to mark our chart on? I haven't a bit of paper."

Here was another difficulty. It would be impossible to make tracings on their clothing. Harry's wit came to the rescue. "I have it. Why can't we break off a piece of this chalk. Probably we can find some smooth piece that will answer."

"That might be done," was George's answer, on reflection; "but what can be used to mark on chalk?"

The Professor was now highly amused. "Can't you think of anything we have here which will answer?"

"I haven't had a pencil, or anything except charcoal, since we touched this wonder island."

"We have something here that is used among all civilized people the world over for marking purposes." The boys opened their eyes in wonder. "I have it here," said the Professor, looking at the lamp.

"The lamp?"

"No, not the lamp, but what is in the lamp."

"The oil? Where can we get anything to mark with in the oil?"

"We have been making a marking material all the time we have been in the cave, and you are just as well acquainted with it as anything you know. It is the soot from the burning oil."

The boys laughed, not at the information, but at their stupidity.

"Yes; the soot is carbon, and the best soot is made by imperfectly burning oil, or fat, or any other fuel which has a large amount of carbon."

The boys found several pieces of flat chalk, one of them a little over a foot long. This was held above the flame of the candle until covered with soot.

"The first thing to do is to establish a base line. This we will mark A on the drawing. Now, starting from the point here where we lost the light, you may measure along the line to the west, we will say, until you get to the other end of the chamber. Twenty-five measures of the spear? That makes the chamber 125 feet long, and it is about 90 feet the other way. Let us roughly outline the floor plan. Now go out toward the mouth of our cave, and measure off 50 feet. Stop there. You see, I have marked the line A and have laid down the slate slab so that this line is exactly on a line with the one you have measured along the chamber. The point B, 50 feet from here, which you have just measured, makes an angle, C. I will now take the slab to the point B, and you may measure off 50 feet more, and we will call that D. That gives us another angle line, E. You see, at every point we establish a new base line. C is the base line for the line E, and so on all through the cave."

Fig. 32. The Cave, and how it was charted.

All the measurements were made on the plan outlined, and scratched on the sooted slab.

"One thing more we must observe. As we are marking the successive points, you will notice that I took particular care to observe the side walls of the passageway, so that I could roughly outline them, noting the distances from the various points, and in a crude way marking out the irregularities between the points."

The chart interested the boys so intensely that the disappearance of the light did not again recur to them until they emerged from the mouth of the cave, when it all came back again, with added wonder and speculation. How many more mysterious things would present themselves!