"I certainly do not mean that, and I hope you will keep it up,"
interposed the surgeon.

"Then I will say that the canal is run on the 'block system,' except on
the lakes, where the ships can go at full speed," added the commander.

"Where are the blocks? I don't see any," said Mrs. Blossom.

"They are all along the canal."

"I don't know what is meant by the block system," added Mrs. Belgrave.

"The railroads in England and the United States, or many of them, are
run by this method. The whole length of the road, or canal in this case,
is divided into short sections. On the railroad no train is permitted to
enter a section till all other trains are out of it, and a collision is
therefore impossible. The system is controlled by telegraph, by which
signals are ordered at either end of the division. On the canal the
director at Port Tewfik controls the movements of every ship on its
passage either way. These posts mark the sections. You will learn more
of it when we get to the other end of the canal."

The breakfast gong sounded at this time, and the party were not so eager
for knowledge as to pass over the morning meal.

CHAPTER XXII

THE CANAL AND ITS SUGGESTIONS

The tourists had been up long enough to be in excellent condition for
breakfast; and the Asiatic breezes from the south-east were cool and
refreshing, for they came from the mountains of the peninsula of Sinai,
where Moses had received the law from Heaven. There was something
inspiring in this thought to the minds of the more religious members of
the party when the commander announced the proximity of the sacred
mountain after he had asked the blessing.

"How far is Mount Sinai from where we are now?" asked Mrs. Woolridge.

"I cannot tell you just how far it is at this moment, for my charts are
in my cabin," replied Captain Ringgold. "We are not so near it as we
shall be later; but you will all see it after we get into the Red Sea.
We will defer the subject till that time; and I should not have
mentioned it if the south-east wind had not suggested it."

"I got a glance at an enormously big steamer ahead of us just as we were
leaving the promenade," added Mr. Woolridge. "She looked as large as
Noah's Ark, and appeared as though she was sailing over the land."

"Perhaps she was quite as large; for the pilot tells me that the Ophir
is just ahead of us," added the commander.

"What is the Ophir?" asked Mrs. Belgrave.

"She is the largest