"Easily," said Mike. "Look up yonder: we can take those two pieces of rock up on the ridge for our bearings. They stand as two ends of the base A B, as Mr Deane would say, and if you draw lines from them they will meet here at this point, C. This hole's C, and we can't mistake it."

"No. But look here: this is better still. Look at that bit of a crag split like a bishop's mitre."

"Yes: I see."

"We've got to get this laid-down rock in a line with it, and there are our bearings; we can't be wrong then."

"No," cried Mike. "Who wouldn't know how to take his bearings when he's out, and wants to mark a spot! Now then, is it lay our heads for home?"

It was a long while before either of them slept that night for thinking of their discovery, and when they did drop off, the dark, tunnel-like place was reproduced in their dreams.

CHAPTER NINE.

STUDY VERSUS DISCOVERY.

"Dear, dear, dear, dear!" in a tone full of reproach, and then a series of those peculiar sounds made by the tongue, and generally written "tut-tut-tut-tut!" for want of a better way--for it is like trying to express on paper the sound of a Bosjesman's _click cluck_ or the crowing of a c.o.c.k.

The speaker was Mr Humphrey Deane--a tall, pale, gentlemanly-looking young university man, who, for reasons connected with his health, had arranged with Sir Francis Ladelle and the Doctor to come and stay at the Mount, where he was to have a comfortable home and the Doctor's attendance, a moderate stipend, and, in exchange, to help on the two lads in their studies every morning, the rest of the day being his own.

The plan had worked admirably; for Mr Deane was an earnest, able man, with a great love of learning, and always ready to display a warm friendship for boy or man who possessed similar tastes. The lads liked him: he was always firm, but kindly; and he possessed that wonderful power of imparting the knowledge he possessed, never seeming at a loss for means to explain some puzzling expression in cla.s.sic lore, or mathematical problem, so as to impress it strongly upon his pupil's mind.

The morning he uttered the words at the beginning of this chapter he was seated with the two boys in the long, low library at the Mount, whose heavy windows looked out upon a great, thick, closely-cropped yew hedge, which made the room dark and gloomy, for it completely shut off all view of the western sea, though at the same time it sheltered the house from the tremendous gales which swept over the island from time to time.

It was the morning after the discovery in so unpleasant a manner of the hole at the foot of the slope, and their projected visit of investigation in the afternoon so filled the lads' heads that there did not seem to be any room for study; and, in consequence, after patiently bearing the absence of mind and inattention of his pupils for a long time, the tutor began to be fidgety and, in spite of his placid nature, annoyed.

The Latin reading and rendering went on horribly, and the mathematics worse. Vince tried hard; but as soon as he began to write down _a_ + _b_--_c_ = the square root of _x_, his mind wandered away to the rocks over the Black Scraw. For that root of _x_ was so suggestive: _x_ represented the unknown quant.i.ty, and the Black Scraw was the unknown quant.i.ty of which he wanted to get to the root; and, over and over again, when the tutor turned to him, it was to find the boy, pen in hand, but with the ink in it dried up, while he sat gazing straight before him at imaginary grottoes and caverns, lit up by lanthorns which cast the black shadows of two explorers behind them on the water-smoothed granite floor.

But this did not apply only to Vince, for Mike was acting in a similar way; and at the end of an hour Mr Deane could bear it no longer, for it had happened at a time when he was not so well as usual, and it required a strong effort of will to be patient with the inattentive lads when suffering pain.

And so it was that at last he uttered the "dear dears" and "tut tuts,"

and roused the two boys from their dreams about what they would see in the afternoon.

"Are you unwell, Vincent Burnet?" he said.

"Unwell, sir?--oh no!" said the lad, colouring a little.

"You seem so strange in your manner this morning; and Michael Ladelle here is the same. I hope you are not both sickening for something."

"Oh, I'm quite well, sir," said Mike hurriedly. "Perhaps it's the weather."

"Perhaps it is," said Mr Deane drily. "Now, pray get on with those problems."

"Yes, of course," cried Vince; and he began to work away most industriously, till, as the tutor was resting his head upon his hand and looking down at the paper upon which he was himself working out the problem he had set the boys, so as to be able to show them, step by step, how it was best done, Mike scribbled something on a sc.r.a.p, shut it in a book, and pa.s.sed it to Vince, after glancing across the table and then giving him a nudge.

Vince glanced across too; but Mr Deane was apparently intent upon the problem, his delicate right-hand guiding the new quill pen, and forming a long series of beautifully formed characters which were always looked upon by the boys with envy and surprise.

Vince opened the book at the sc.r.a.p of paper and read:

"I say: let's tell old Deane, and make him go with us."

Vince turned the paper over and wrote:

"What for? He'd spoil it all. Want to knock all the fun out of our discovery?"

The sc.r.a.p was shut up in the book and pushed back to the sender; the work continued, and then came another nudge and the book once more, with a fresh sc.r.a.p of paper stuck in.

"I say, I can't get on a bit for thinking about the Black Scraw."

Vince wrote on the back:

"More can I. Get on with your work, and don't bother."

This was forwarded by library table post, and then there was nothing heard but the scratching of the tutor's pen. But Mike's restlessness increased: he fidgeted and shuffled about in his chair, shook the table, and tried all kinds of positions to help him in solving his algebraic problem, but without avail. Scrub oaks, ravens and red-legged choughs danced before his eyes; great dark holes opened in the rocks, and the desire to finish work, get out in the bright sunshine, and run and shout, seemed more than he could bear.

At last, to relieve his feelings a little, he took a fresh piece of paper, laid it over his pluses and minuses and squares and cubes, and then wrote enigmatically:

"Lanthorn and rope."

This he blotted, glanced at the hard-working student across the table, and then thrust it sidewise to Vince, who took it, read it, and, turning it over, wrote:

"You be hanged!"

He was in the act of blotting it when the pen dropped from Mr Deane's fingers; he sat up, and extended his hand as he looked sternly across the table.

"Give me that piece of paper, Vincent," he said.

Vince hesitated; but the tutor's eyes gazed firmly into his, and wrong yielded to right.

He pa.s.sed the paper across to Mr Deane, and then nearly jumped out of his chair, for Mike gave him a violent kick under the table.

"To be paid with interest," thought Vince.

"Oh! you jolly sneak, to give it up!" thought Mike, as the tutor read the paper on both sides.

"I am very sorry," he said, after coughing to clear his voice--"very sorry to have to exercise my authority towards you two, who have been acting this morning like a pair of inattentive, idle schoolboys; but when I undertook to act as your tutor, it was with the full understanding that I was to have complete authority over you, and that you were both to treat me with proper respect."

The boys sat silent and feeling horribly guilty. If Humphrey Deane had been an overbearing, bl.u.s.tering personage, they might have felt ready to resent his words; but the injured tone, the grave, gentle manner of the invalid went right home to both, and they listened, with their eyes upon their scanty display of work, as the tutor went on.

"You both know," he said, "that my health will not permit of much strain, but so long as you both work with me and try your best, it is a pleasure to me, and no one could feel more gratification than I do when you get on."

"Mr Deane," began Vince.

"One moment, and I have done," continued the tutor. "You well know that I try to make your studies pleasant."

"Yes, sir," said Mike.