The chart was easy to understand. Chris Travers recognized it immediately, and his heart seemed to stop for a moment as he did.
Their first step had been the dirigibles: their second was a blow which paled the other into insignificance. And Chris told himself desperately:
"It can't go through! It can't!"
The lines on the cardboard were a detailed map of the Panama Canal; and the black arrow pointed unerringly to its most vulnerable, unguarded and vital point, the Gatun Spillway, which, if wrecked, would put the whole intricate Canal hopelessly out of commission.
Istafiev was speaking again, in low, terse tones, oblivious of the desperate resolve forming in Chris's brain.
"Only one of the dirigibles had been destroyed. Well, it iss too bad, but not fatal to the plan. The ZX-1 can hamper our country's operations when she strikes, but if the ZX-2 were also in action, they would be hampered much more—perhaps fatally. It iss not serious. So we go ahead. Now, Kashtanov, for the last time, the scheme of wrecking Gatun Spillway iss this:
"Note, here, the small golf course. That iss your landing space. You know its location: a mile, perhaps, from Gatun Dam and the spillway. At night, there iss no one near it or on it. You drop down to the golf course from seven thousand feet: the helicopter motors are muffled, and no one will hear you come. Some of the stretches of the course are secluded and hidden by the surrounding jungle; choose one of these to land on. Well, that iss easy.
"The spillway iss about midway in Gatun Dam: its channel has been cut through a hill. You come along the side of this channel right up close to the spillway—close, remember!—and leave the box there. The range of the rays, you know, iss two hundred feet: set them to fire one minute after you leave the box. They will destroy the seven gates of the spillway and also part of the dam and the hydro-electric station. Gatun Lake will then empty itself; the canal will be half drained; the power will be gone—it will take half a year to repair it all. The ZX-1 can fly up to the east coast, thanks to Zenalishin's fumbling—yess; but these American fleets are massed in the Pacific; they will have to go around South America to reach the Atlantic—and that will take weeks.
"And in that time the Soviet has crossed the Atlantic uncontested and has paralyzed the heart of America, her eastern states. Ah, it iss magnificent!"