It was moving.
"The principle of the thing," said Captain Shirley, talking to us but watching the moving light intently, "briefly, is that I use the Hertzian waves to actuate relays on the Z99. That is, I send a child with a message, the grown man, through the relay, so to speak, does the work. So, you see, I can sit up here and send my little David out anywhere to strike down a huge Goliath.
"I won't bore you, yet, with explanations of my radio-combinator, the telecommutator, the aerial coherer relay, and the rest of the technicalities of wireless control of dirigible, self-propelled vessels. They are well known, beginning with pioneers like Wilson and Gardner in England, Roberts in Australia, Wirth and Lirpa in Germany, Gabet in France, and Tesla, Edison, Sims, and the younger Hammond in our own country.
"The one thing, you may not know, that has kept us back while wireless telegraphy has gone ahead so fast is that in wireless we have been able to discard coherers and relays and use detectors and microphones in their places. But in telautomatics we have to keep the coherer. That has been the barrier. The coherer until recently has been spasmodic, until we had Hammond's mercury steel-disc coherer and now my own. Why," he cried, "we are just on the threshold, now, of this great science which Tesla has named telautomatics—the electric arm that we can stretch out through space to do our work and fight our battles."
It was not difficult to feel the enthusiasm of the captain over an invention of such momentous possi-
