This was pleasing to the boys, who liked Sutoto.

"And who are the others that went with him?"

"Why Lolo was one of them, and Stut and Chump. Oh, they had a jolly time; so they said, and I can believe it, because they are simply crazy to make another trip." And the Professor beamed as he related many of the incidents which they told him of their experiences.

While they were talking, Sutoto appeared, and was immediately admitted.

After some talk, Sutoto said: "The Professor said that when you returned you would have some work for me with the _Pioneer_."

"Yes, and you shall command her," said Harry.

Sutoto could not but show his pleasure. "I knew you would come back, but so many here said you would not."

At this point Professor explained that there were many rumors among the people to the effect that the boys would never again come back, and all showed grief at the news. I a.s.sured them that you were just as anxious to return as they were to have you and I then told Sutoto that I knew you had plans which would require his services, but I thought it would be more agreeable if you imparted the nature of it to him.

The boys were not slow to outline the plans to him, but advised him to keep the information to himself, which he promised to do. It was enough for him to know that he would command the ship. It was this that induced Sutoto to take out the ship, and finally to circ.u.mnavigate the island, so as to try out the sailors and properly to fit them for the work when the boys returned.

"Now that being settled, Sutoto, we are going to leave the work of provisioning the _Pioneer_ to you. We must take a supply of guns and ammunition, as well, and probably it would be wise to have a small troop of the best soldiers," was Harry's instruction.

"Uraso wants to go. I am sure he would be the best one to take.

"What will Muro say to that?" asked the Professor.

"Oh, take him along, by all means," said George, "because I want Lolo to go with us."

It was then settled that they were to take a small force, sufficient for immediate purposes, and if it was found that the islands discovered were too well settled with hostiles it would be an easy matter to remain aloof, or return for reinforcements.

While arrangements were being made for the departure of the expedition Blakely informed the Professor that it would be good policy to make up part of the cargo of the _Wonder_ with copper, and that both vessels could proceed to the southeastern part of the island, and the men aboard could be used to transport the copper to the sea.

In this way the expedition would serve a double purpose. No one attempted to go contrary to the wishes of Blakely on matters which touched upon the commercial ventures in which they were engaged.

John was only too glad that Blakely had hit upon that idea, as he was anxious to visit that part of the coast, contiguous to the copper deposit, and what was more, he wanted to see the place where Blakely found the missive which the boys had translated.

As there was still a week before the _Wonder_ would sail for its northern port of call, both of the ships wended their way to the east, skirting the coast as closely as possible, John on the _Pioneer_ with the boys.

They now had an opportunity to see the Great South Mountains from the sea. They remembered when they last saw them on land, during the campaign against the Illyas, and also the wonderful village on the western side of the mountains. What would their present wanderings bring forth?

That evening they landed within a cove, both vessels being brought as near the sh.o.r.e as possible.

"We can safely go in close this evening, because the tide is now out,"

said John.

Sutoto, while he had navigated the vessel, and had shown remarkable skill, was, nevertheless, not well versed in tides and the action of the moon.

Quick to learn, he asked John why the tides thus changed. John explained the reason that the tides flowed in and out twice during each twenty-four hours, or a little less than that time, so that high water, or low water would always be at a time a little later each day, and then stated that it would be an easy matter to so make the calculations that they would be able to tell ahead for a whole year just when during each day the highest or lowest water would be.

While waiting on the ship during the hours of the evening they were interested in the magnificent fire flies which they saw on the sh.o.r.e and along the mountain side. This was not an unfamiliar sight to them as they had witnessed such scenes many times before.

But now they saw such sights as they had never before observed. They must have been giant glow birds, because some of the lights flew at least hundreds of feet emitting continuous streams of light, and this was not all, many of the lights were colored, particularly red and blue or simply faint tinges of those tints.

"I have often thought that there is nothing more wonderful than the fire fly," said George.

"But what do you think makes it so wonderful?" asked John.

"Well, I suppose the wonderful part is that it has strength enough to make a light," answered Harry.

"No, the remarkable thing is that the light which it emits is absolutely cool. Experiments which have been made go to show that there is no heat.

In every form of light which man has been able to produce thus far artificially, a great heat is evolved, and it would be a most valuable discovery to find out why these insects are able to do it without raising the temperature."

[Ill.u.s.tration: _Fig. 3. The Fire-fly._]

"But what difference does it make if heat is produced?" asked Harry.

"The production of heat means the loss of power. The heat generated takes up more of the power than the light which is produced, so that it would be a great economy if the heat could be dispensed with."

"But if there was no heat in the light produced would it make any difference in the lamps themselves?"

"Unquestionably. The lamps would last much longer."

"What are the things which must be learned in order to get the secret of cold light?"

"Well, there are number of questions which must be determined. While it is known that the fire fly and the glow worm emit what is called a phosph.o.r.escent light, this fact is a mere prelude to the knowledge of what is the exact color of daylight."

"Color of Daylight? Why, I supposed it was white."

"But the light of the glow worm and fire fly are not white."

They watched them, and soon appreciated that John's statement was true.

"You asked what were some of the things to be solved? Well, to find out the secret of the phosph.o.r.escent glow. That is one thing. What is the best artificial light, is the next. Then, what substance will have the most intense glow when a current pa.s.ses through it, and give out the least heat."

"Well, has no one attempted to explain any of these things?"

"Yes; many explanations have been offered, but all of them leave the subject dark somewhere." And John laughed as he saw that the boys appreciated his little attempt at witticism.

"But the time will come when man will find out this, as everything in his way. When you think of it, that electricians, chemists, metallurgists, physiologists, engineers, physicists and microscopists, are all working on the problem, we should be able to extract the secret sooner or later."

"I am going to have some of those fellows," shouted George, and when the natives on board heard the request of George there was a scramble for the boats, and John was delighted to give them instructions for capturing the insects.

Early the next day the entire party landed, and Blakely, together with John and the boys, started for the high peak, the one visible for miles from the west, and which John and the boys often wished to visit.

One of the things which the boys brought with them from the States, was a pair of strong gla.s.ses, and these were constantly in use.

"What do you say to scaling that point?" said Harry.

"Just what I have been thinking about," said George.

Sutoto, who was with the party, showed by his glowing eyes that he wanted to be of the party. "Certainly you shall go," said Harry.