 What is ironic about the Earthmen selling gas to the Zurians?
By this, he seemed to imply that the Thorabians would rob the Earthmen, which the Lorians would not. Immediately, the Earthmen established what they called "corporations"—Zurian trading companies under terrestrial control. For another, the Earthmen had procured legal authority to prospect the planet for metals, of which they found a good deal, but they told no one on Zur of this. Moreover, the Earthmen sold the Zurians their own natural gas at a nice profit and everybody was happy with the situation except the brothers Masur. This was Earth's first step toward flooding Zur with the natural follow-up in its campaign of advertising—radio programs—with commercials.
 The gas was collected on Zur
 The gas was collected on Zur  The gas is from Earth and will not power Zurian machines  The gas will be replaced by a new type of gas that Zurians will need to purchase in the next decade  The Earthmen are not selling gas; rather, a material that causes machines to break