THE BIRTHDAY PARTY; AND THE SURPRISE
You may be sure that the interesting topic of conversation that night
had relation to the events of the day. All previous experiences were
insignificant now in comparison. Every phase of the question was
discussed, and a solution sought.
The Professor did not attempt to conceal his doubts. "I have a theory
that we are or may be near some other island, possibly inhabited by
white or civilized people. It is likely that people from those islands
may visit this place at intervals, and that the boat which we left at
the falls was really washed down to the sea and found by some of them."
"If that is the case, why should it be washed up on shore, as it was?
They, no doubt, used the boat, as the oars and rope showed. But I can't
possibly make out the meaning of its being in the driftwood."
"That boat we made is a hoodoo," was Harry's conclusion. "Twice lost is
enough for me."
"Well, I would take a sail in it the next day if we could only find it."
"I am interested in it," observed the Professor, "not so much for the
purposes of its use, as to enable us to find out something more about
it, and how it came to be there. If it had occurred to me that we should
lose it so soon you may be sure I should have made a more careful
examination of it when we had it. But it is too late now."
Harry's solution was the one most acceptable. "Let us make another boat,
and with that we can carry on our investigations more satisfactorily."
"Harry is right. A good vessel will be a measure of safety, in the event
we should be attacked by savages, and it will at least enable us to
visit the shore line of our continent."
The sanitary arrangements of their kitchen had been for some time very
unsatisfactory, and somewhat cramped, and the Professor thought it would
be wise, for their comfort and health, to cleanse it thoroughly.
"I am inclined to think that Harry's sickness was caused by the
condition of the kitchen. We are apt to overlook these things in the
multiplicity of our work."
"What is the best way to clean it, by washing?"
"That is necessary, of course, but it is impossible, even by a liberal
use of hot water and soap, to remove many of the poisonous germs. Some
good disinfectant should be used."
"Have we anything which could be used for the purpose?"
"There is nothing better than charcoal. Common wood charcoal has the
capacity of purifying and rendering odorless almost all impurities."
"In what way does charcoal do this?"
"When charcoal is crushed up finely its remarkable porosity enables it
to absorb an enormous quantity of gases, and when so absorbed it
condenses them, in which condition they are harmless, or they are
retained in the charcoal."
"But how about the impure liquids?"
"Its affinity for sour and stinking liquids is so great that two
tablespoonfuls of charcoal will purify a pint of the foulest sewage; it
will also, in that quantity, absorb 100 cubic inches of gaseous
ammonia."
"Have we anything else that can be used?"
"The sulphur that is in the samples of copper ore, if burned, will make
a sulphurous acid gas, and while it must be carefully used, on account
of its noxious and offensive odor, is a most powerful germicide. Or if
we take some of the green acid of the copper, and make a liquid of it,
and then pour this over common salt we are making what is known as
muriatic acid. The vapor of this acid will destroy all germs. The
objection to this, however, is, that it has an odor which is worse than
the impure or unhealthful gases. In the last samples of ore we brought
home, you may have noticed a very black lot of stuff. That was
manganese. If we take the muriatic acid, which I have just referred to,
and pour it over the manganese, we can make the most powerful agent of
all, namely, chlorine."
"Chlorine is used for bleaching, isn't it?"
"That is its great use in the arts; but as a purifier it has no equal.
It will decompose every gaseous compound and evil-smelling gas which
escapes from decayed animal or vegetable matter."
Harry did not let the Professor forget the matter of the primary
electric battery which he had been making preparations for, and after
they had gone over the sanitary features of their kitchen, he was
anxious to make a start. George was equally insistent, because the
question of a better light was ever uppermost in his mind.
"Then here goes for the primary battery. We haven't any glass, nor have
we found any rubber lying around, so we can make cells out of them, so
what shall we use?" was the Professor's first inquiry.
"Why not use some of these iron pots we made?"
"I am afraid iron would not last very long, with sulphuric acid in them.
We should use some non-conductor of electricity."
"What do you mean by non-conductor?"
"That quality in a material which will not allow electricity to pass."
"Then why can't we use clay? Will that conduct electricity?"
"That is just the thing. Isn't it wonderful what a friend common clay
has been to us since we have been on this island!"
"I think we ought to erect a monument to Monsieur Clay?"
"It would be a fitting thing to do, because at the end we are all bound
to go back to him."
"I believe you said, Professor, that we should have to grind up the coke
and then mix it up and make plates out of it?"
"Yes; we can use either carbon or copper for the negative plates."
"What are the other plates?"
"The positive. That is what I wanted the zinc for, which we made several
weeks ago."
"Why should we have positive and negative plates in a battery?"
"Everything must have an opposite. If there is an up there must be a
down; there would be no darkness without light; no heat without cold; no
strength without weakness, and no joy without sorrow. Like all these
things, the electric current flows from one to the other."
"But in electricity the current flows only one way, does it not?"
"In the primary battery that is the case; but when electricity is
generated and sent over the wires, the natural current flows in both
directions--that is, it goes in one direction as much as in the other."
"I do not understand what you mean by that."
"The current alternates. What is meant by that is this: For an instant
the current flows from the positive to the negative, and the next
instant it flows from the negative to the positive, and so on, making
the alternate current."
"Then the primary battery we are going to make will be another kind of
current?"
"We shall make what is called the direct current which goes in one
direction only--that is, within the battery it moves from the positive
plate, the zinc, to the copper plate, or negative, and outside of the
battery it moves from the negative to the positive plate."
"Why does it do so?"
"In order that you may understand, I shall make a drawing so Harry will
not have so much trouble in arranging the parts. So if you will examine
the sketch (Figure 25), you will see that the clay cell, which we are to
make, has in it the two electrodes, A and B. That is what they are
called when they are spoken of together; but the positive one (A), the
zinc, is called the anode, and the negative (B), or copper, is called
the cathode. You should keep these terms in mind.
[Illustration: _Fig. 25. PRIMARY BATTERY_]
"The liquid in the cell, marked C, is used as the electrolyte, and for
that we shall take some of the sulphate of copper which the copper ore
furnishes. A good strong salt solution would also answer the purpose.
The two electrodes are separated, and a wire connects the two outside of
the cell. Now you will notice that within the cell the current flows, as
shown by the dart E, from the positive to the negative plate, but
outside of the battery the current flows through the wires F from the
negative to the positive plate."
"I can understand it now. The current from the battery will always go
from the negative to the positive pole."
"You are mistaken. I am glad you referred to that. It shows the
importance of using correct terms. You must not confound the terms
'negative plate' with 'negative pole.' All currents leave the battery or
dynamo from the negative plate, but that negative plate is called the
positive pole of the dynamo."
"It seems to me that is a curious way to do it."
"Such is the case, however; but there is no real positive or negative in
the alternating current, so that either side may be termed positive or
negative."
Work on the battery continued for some days, as lack of fine tools made
much of the work difficult, and in doing this work, as in everything
else, a certain amount of preparation was necessary. They had no screws,
and no facilities for making them, so a substitute had to be devised,
but the difficult part now to encounter was the preparation of the wire.
"A battery is of no use unless we can have wire, and it will be a big
job to beat out wire long enough for our purposes," Harry observed as
the battery neared completion.
"Then we must draw some wire?"
"From what?"
"From the copper?"
"Is that better than iron?"
"Copper should be used for several reasons; first, because electricity
travels through a copper wire more easily than through iron, and second,
for the reason that copper is more ductile than iron, and can be drawn
into a wire with greater facility."
"Doesn't electricity flow through different substances at the same rate
of speed?"
"Yes; but it retards the amount or the force."
"You say, 'Amount' or 'Force.' I can understand that if applied to
water, that there might be a large or small quantity of water, or a
greater or less pressure, but I do not see how this applies to
electricity."
"In measuring the pressure of water, calculation is made by taking the
height of the water in the tank. For every 28 inches in height a column
one inch square weighs one pound. This represents the force of the water
when it issues from the orifice below. Now the orifice may be large or
it may be small. The amount or quantity which flows out is dependent on
the size of the opening. Electricity is measured in a somewhat similar
manner. What is called 'Volts' is the same as the force in the
tank--that is, voltage means the pressure. Amperage, on the other hand,
refers to the amount of current which is passing, and a greater quantity
will pass over a large wire just the same as a greater amount of water
will flow through a large than a small pipe. Is this perfectly clear to
you?"
"Yes; I understand the difference, now."
The drawing of wire is not a difficult task where facilities are at
hand, but it must be remembered that all their tools were of the crudest
kind. Harry had prepared a number of bars of copper, each having been
beaten out to form pieces about ten inches long and a half inch thick. A
steel plate about three-eighths of an inch thick, two inches wide, and
six inches long, had a number of holes bored through it, the largest
hole being a half inch in diameter, and gradually increasing in size,
the smallest being about a sixteenth of an inch in diameter.
[Illustration: _Fig. 26. Template for Drawing Wire._]
When all was ready Harry was instructed to hammer out one end, so it
would go through the largest hole. The projecting end was then grasped
by a pair of heavy pliers, and pulled through, so that the bar was
formed the size and shape of the first hole, and of course the bar was
lengthened. The end was then hammered out so that it would go through
the next smaller hole, and the same process was repeated, and when the
wire got larger they had a tool which pushed the wire in at the same
time it was being pulled out at the other side.
It was laborious work, and a long time was consumed in fully drawing out
each bar. In this way a quantity of serviceable wire was prepared.
"Why does this plate get so hot when we pull the wire through?"
"Why do you make a fire by rubbing together two substances?" replied the
Professor.
"On account of the friction."
"For that same reason you are making the heat in drawing the copper
through the die."
"But I notice that if I hammer a piece of cold iron it will get hot.
There is not any rubbing motion there to make friction."
"Do you think not? You have by that means made the most intense
friction. The iron is composed of tiny particles, called atoms, and
molecules. When you strike a piece of iron you force these particles in
among themselves, and the friction caused by this movement produces the
heat."
"Is that true of all substances?"
"Yes."
"Well, if air is forced together will it heat in the same way?"
"Yes, and for the same reason. The tiny particles, of which air is
composed, move among each other with such rapidity, under compression,
that the heat their frictional contact develops is dependent on the
pressure exerted."
"You used the terms 'atom' and 'molecules' a moment ago. What is the
difference between them?"
"A molecule is always composed of two or more atoms. An atom is smaller
than a molecule, for this reason. Furthermore, an atom comprises only
one substance. A molecule has two or more substances in its make-up. For
instance, water is composed of two parts of hydrogen and one part of
oxygen. One molecule of water, therefore, has three atoms, two of the
atoms being hydrogen, and one atom oxygen."
"Baby," the infant orang-outan, had now grown to be a pretty good-sized
boy. He would sit at the table and gravely eat with a knife and fork,
which he had learned to handle most intelligently. In the various trips
which had been made from time to time, the Baby was kept at home, but on
more than one occasion he would follow up the wagon, and would as often
be welcomed when he did come.
Harry found a good use for him later on, and from that time forward Baby
knew that a jaunt into the forest meant a trip for him as well. When it
came to tree climbing Baby was in his glory. He would swing from branch
to branch, and shake the nuts, and the amusing thing was to see him help
gather and throw the nuts into the wagon, in the most business-like
fashion. He was never known to laugh, but they had many occurrences
which, no doubt, made him smile in his own way.
George was an adept cook. He was fond of making surprising delicacies,
and boy-like, they were always the kind that had honey of some sort in
their composition. Without any knowledge of cooking, but knowing, in a
general way, that eggs and milk were the principal things used in
puddings, it was not long before he was regarded as the chef. Baby was
sure to be present whenever George occupied the kitchen. And help! Why
certainly! He knew what flour meant, and particularly honey. The truth
is, that he knew what that meant if George merely looked in the
direction of the honey pot.
And talking about eggs! Harry found out about this accomplishment in
Baby. In the tall grass beyond the barley fields were flocks of prairie
chickens, and during one of the hunting expeditions he found several
nests of eggs. They are just as much more delicious than the common egg
as the prairie chicken is more delicate than the hen. Baby never
thereafter forgot the eggs. Singularly, he never ate any of them.
Apparently the orang does not crave them in his native state, but the
little rascal had an eye to the good things, and when he saw the eggs go
into the pudding and cake, there were no scruples on his part.
George had been planning a surprise for the Professor. In many devious
ways he learned his age, and August was the month, so in concert with
Harry, planned to treat the Professor with a birthday party, the first
real attempt at jollification which had been proposed since they landed.
"I remember, he said he would be sixty-five years old on the tenth of
August."
"But the trouble is, we don't know when we get to the 10th of the
month."
"The chances are he doesn't know, either. But what difference does a day
or two make, anyway?"
Among the delicacies which George had prepared were 65 little sweet
cakes, because they couldn't put that many candles on the big cake, and
the boys knew, from experience, that they would have to use candles, or
something else to typify the age.
The "tenth of August" came, and the Professor, in all innocence,
proposed a day for hunting. Both boys opposed this, to his surprise. The
Professor did not press the matter. As usual, when at home, he was shut
up in what they called the laboratory. Even though he should be present
in the kitchen he would not be likely to take notice of any extra
preparations.
In the meantime Harry had made a bell out of a flat sheet of steel. It
was really a gong. When the noon hour arrived and the table had been set
ready for the symbolic cake pyramid of little cakes, George ordered the
gong to sound, and Harry made such a frightful din with the unexpected
noise, that Baby was terribly frightened, and scampered to the loft, his
usual place of retreat when reproved or unduly excited.
The Professor was out of the laboratory like a shot, and hurried over to
the house. At the same time George returned. "Who has taken my cakes?"
he cried. "There are less than a dozen left." Baby chattered in the
loft. The Professor could not understand the commotion. All he knew was
that Baby was swinging along the rafters and that George was flying
around the kitchen hunting cakes.
"Hello, and what is all this? Expecting company?"
"Yes; this is a birthday party."
[Illustration: _"'What is this, a party?' said the professor. 'Yes, a
birthday party,' said Harry"_]
"That is a good idea. I suppose you have invited all your friends?"
"Yes; we have invited all we know; just one."
The Professor did not need to be told any more than this. His eyes
filled with tears, the first real thing that the boys ever saw on his
part that strongly affected them, and when the Professor, his heart so
full that he could not speak, silently looked at them, they forgot the
feast, and the cakes, and Baby. They thought of home and of what they
were doing there, and whether the time would ever come when they might
be rescued.
Brave Harry was the first to recover. Like a veteran he grasped the
Professor by the hand, and wished him many a happy return of the day,
and George, though not so demonstrative, joined Harry in this wish and
prayer. Just then one of George's cakes fell at his feet. He picked it
up and Harry glanced at the Baby. The mysterious disappearance had been
solved.
No! Baby was not spanked. He came down without any coaxing, with several
of the cookies in his hand, and gravely took his place at the table.
What a very narrow margin there is between tears and laughter. They
roared as though such a thing as tears were unknown.
When they recovered from their fits of laughter, and attempted to
proceed with the feast in some semblance of order, a glance at Baby was
sufficient to start them up anew. And here a surprising thing occurred.
As before stated, he never had been known to laugh. But now Baby
laughed, for the first time. And then the boys and the Professor knew
that this was also the first time they had indulged in a hearty laugh.
"You may say what you please," said the Professor, "but laughter is
infectious. How much farther a smile will go than a frown. And this
reminds me of a very curious thing in nature. What are called perfumes
have been known to carry through the air for ten miles. The odor from
the balsam-yielding Humeriads has been perceived at a distance of four
miles from the shores of South America; a species of Tetracera sends its
perfume as far as that from Cuba, and the aroma of the Spice Islands is
wafted many miles to sea. Now the singular thing is, that vile and
injurious odors are not carried such distances."
"Why not?"
"For the reason that the oxygen of the air destroys the bad odors."
"I thought of this when we were laughing here so merrily a while ago.
Laughter is like a perfume, it goes a long way and does not need a
purifying agent; but the harsh and angry word is like the evil smelling
substance, which needs to be purified."