minus twenty-second grams, rest
mass, can come galumping along at a velocity so close to that of light
that the kinetic energy is something colossal for so small a particle.
Protons with a kinetic energy of ten to the nineteenth electron volts,
while statistically rare, are not unusual.

Now, ten million million million electron volts may be a wee bit
meaningless to the average man, so let's look at it from another
angle.

Consider. According to the well-known formula E = mc^2, a single gram
of matter, if converted _completely_ into energy, would yield some
nine hundred million million million ergs of energy. An atomic bomb
yields only a fraction of that energy, since only a small percentage
of the mass is converted into energy.

If _all_ of the mass of an atomic bomb were converted into energy, the
test in Alamogordo, New Mexico, 'way back in 1945, would probably have
been the last such test on Earth; there wouldn't have been anyone
around to make a second test.

So what does this have to do with cosmic ray particle? Well, if that
atomic bomb had been moving at the velocity with which our
ten-to-the-nineteenth-electron-volts proton is moving, it could have
been made of sand instead of U^235. It would have produced ten
thousand million times as much energy as the total disintegration of
the rest mass would have produced!

Kinetic energy, my children, has a great deal more potential than
atomic energy.

But we digress.

What has all this to do with Jayjay Kelvin?

If Jayjay had been a detective story addict instead of a Western story
addict, he would have heard of the HIBK or "Had I But Known" school of
detective writing. You know: "Had I But Known that, at that moment, in
the dismal depths of a secret underground meeting place, the evil
Chuman-Fu was plotting...."

If Jayjay Kelvin had known what was going on a few million miles away
from the Pluto-bound _Persephone_, he would have kept his mouth shut.

* * * * *

The cargo-ship _Mordred_ was carrying a cargo of heavy metals sunward.
In her hold were tightly-packed ingots of osmium-iridium-platinum
alloy, gold-copper-silver-mercury alloy, and small percentages of
other of the heavy metals. The cargo was to be taken to the Asteroid
Belt for purification and then shipped Earthward for final
disposition. The fact that silver had replaced copper for electrical
purposes on Earth was due to the heavy-metals industry on Pluto.
Bec