to take up the task of finding our
comrades, whatever the cost may be. If that is your view, we should
proceed with that determination, but let us prepare for it in the best
manner possible. How long will it take to finish the six guns you are
now at?" said the Professor, looking at Harry.

"I will try to have them ready within another week," was his reply.

"In the meantime, George and I will prepare a new lot of powder; and for
your further information, I will state that I have been busy during the
past week in making preparations to extract some lead for bullets."

This announcement was hailed with joy. Heretofore they had to depend on
the iron slugs which had been turned out, and they were not at all
satisfactory, because they lacked the proper weight.

"Which is the lead?" asked George, who was examining the samples.

"It is this bluish-gray sample of galena, which, as you see, looks like
lead itself, and is often mistaken for it; but it is far from being lead
of the kind we can work."

"Why not?"

"Because it is in what is called a sulphide form. Do you remember what a
sulphide is?"

"Yes; it is where it is in combination with something."

"That is a fairly good definition. More or less sulphur is found in all
metals, but when found in large quantities the ore is called a
sulphide."

"How can we get rid of the sulphur?"

"We can cook it and drive it off like steam. Lead melts at a low
temperature, comparatively, about 600 degrees Fahrenheit, so that with
our furnaces it will be a very easy matter to get a pure lead."

During the rest of the day all were in the laboratory, superintending
the preparation for the work, and at the Professor's suggestion the boys
took the team in the morning and brought in over a hundred pounds of
galena to be treated.

Before noon they had forty pounds of a very fine quality lead, and the
work of making molds for the bullets was begun. The Professor, however,
suggested that the boys should devote their time to the construction of
the boat and guns, and it was difficult to decide what was the proper
thing to do first.

The Professor saw the dilemma and had a very earnest conference on the
subject.

"You must not, by any means, be carried away with undue eagerness and a
desire for haste. The first essential of good business is to do
everything in order. It is better to plan carefully every step in
advance, so that you will know just when your energies will be required