entiment that I have overlooked something important. I wish
you would see if you can think of anything I have omitted."

"The only really important thing I have remembered is half a dozen boxes
of the best cigars," I replied.

"Leave them right here in Whiting," he said with emphasis. "We are
carrying only a limited supply of pure air, and we cannot afford to
contaminate it with tobacco smoke. No, sir, you can't smoke on this
trip."

"Then I won't go! Imagine not smoking for two whole months! Do you think
I have sworn off?"

"No, not yet. But you must. It pollutes the air, which we must keep
clean and fresh as long as possible."

"Now, Doctor, you must let me have a good smoke once a day, just before
pumping the air out of my compartment."

"No, not even that. It is impossible to pump all the air out, and what
is left mixes back with what is in my compartment. Once contaminated
with tobacco smoke, we could never get it perfectly pure again."

"Well, may I smoke on Mars, then? I will take them along for that. But,
I warn you, I eat like a farm horse when I can't smoke."

"I have provided plenty to eat, but I know I have forgotten something.
Mention something now, mention everything you can think of, so that I
may see if it is provided for."

"Have you any money?" I asked. "I have changed some into gold, and have
a fairly heavy bag here."

"Oh, yes, I have some gold and silver money, besides a lot of beads,
trinkets, and gaudy tinsel things, such as earthly savages have been
willing to barter valuable merchandise for."

"So you are going on a trading expedition, are you?" I asked.

"Not exactly. I leave all that to your superior abilities. But we may
find these things valuable to give as presents. Many of them are of tin,
and if they do not happen to have that useful metal on Mars, they will
be of rare value there."

We had now reached the little grove where the projectile was hidden. I
proceeded to open the rear port-hole, saying,--

"Let me look inside, and when I see what you have, some other necessary
thing may suggest itself."

"Let me go in first, for I am afraid you will allow the menagerie to
escape," he said, as he peered in by the light of the lantern. A
diminutive fox terrier barked from the inside, and wagged his tail
faster than a watch ticks, so glad he was to see us. The bright light
also awakened a small white rabbit that had been asleep in the doctor's
compartment.

"You are taking th