a lot of their valuable fireworks formulae too."

"And you believe they have yours?" asked Ned.

"I'm sure of it!" was the fierce answer. "Those men are unprincipled
rogues! They had been at me ever since I was foolish enough to tell
them about my formulae to get me to sell them a share. But I refused,
for I knew the secret mixtures would make my fortune when I could
establish a new dye industry. Field and Melling claimed they wanted the
formulae for their fireworks, but that was only an excuse. The formulae
were not nearly so valuable for pyrotechnics as for dyes. The fireworks
business is not so good, either, since so many cities have voted for a
'Sane Fourth of July.'"

"I can appreciate that," said Tom. "But what we called for, Mr. Baxter,
is to find if you have room enough to let me do a little experimenting
here. I am working on a new kind of fire extinguisher, to be dropped on
tall buildings from an airship."

"Sounds like a good idea," said the chemist, rather dreamily.

"Well, I have the airship, and I can see my way clear to perfecting a
device to drop the chemicals in metal tanks or bombs," went on Tom.
"But what bothers me is the chemical mixture that will put out fires
better than the carbon dioxide mixtures now on the market."

"I haven't given that much study myself," said Mr. Baxter. "But you are
welcome to anything I have, Mr. Swift. The whole place, such as it is,
will be at your disposal at any time. I intend to have it in better
shape soon, but I have to proceed slowly, as I lost nearly everything I
owned in that fire. If I could only get those formulae back!" he sighed.

"Perhaps you may recall the combinations," suggested Ned. "Or can't you
get them from that Frenchman?"

"He is dead," answered the chemist. "Everything seems to be against me!"

"Well, it's always darkest just before daylight," said Tom. "So let us
hope for the best. We both have had a bit of bad luck. But when I think
of Rad, who may lose his eyesight, I can stand my losses smiling."

"Yes," agreed Mr. Baxter, "you have big assets when you have your
health and eyesight."

Three days later the eye specialist looked at Rad. Tom stood by
anxiously and waited for the verdict. The doctor motioned to the young
inventor to follow him out of the room, while Mrs. Baggert replaced the
bandages on the colored man's eyes and Koku stood near him,
sympathetically patting Rad on the back.

"Well?" asked Tom nervously, as he faced the