"Yes, sir. India is deeply interested in our grain so it seemed likely that she would cooperate. She could grant us land, make labor and materials available, and so forth. But I mentioned India because she holds a wide choice of possible sites, very high mountains not too far from Terra’s equator. The latter is not essential, just helpful. But the site must be a high mountain. It’s that air pressure you spoke of, or air density. The catapult head should be at as high altitude as feasible but the ejection end, where the load travels over eleven kilometers per second, must be in air so thin that it approaches vacuum. Which calls for a very high mountain. Take the peak Nanda Devi, around four hundred kilometers from here. It has a railhead sixty kilometers from it and a road almost to its base. It is eight thousand meters high. I don’t know that Nanda Devi is ideal. It is simply a possible site with good logistics; the ideal site would have to be selected by Terran engineers."