They stood now almost facetoface, the width of one pitiful little Banana Republic between them. On one hand the Grass, funneled and constricted to a strip of land absurdly inadequate to support its gargantuan might, on the other the combined resources of man, desperately determined to destroy the bridge before the invader. In tropic heat the work was kept up at superhuman pace. Gangs of native laborers fainting under their loads were blown skyhigh by impatient technicians unwilling to waste the time necessary to revive them. In selfdefense the South American states doubled their contributions. At the edge of the weed all the offensive weapons of the world were massed to stay it as long as possible, for even a day's--even an hour's delay might be invaluable. But the Grass overbore the heavy artillery, the flamethrowers, the bombs, the radium, and all the devices in its path. The inventions of war whose constant improvement was the pride of the human race offered no more obstacle to the Grass than a few anthills might to a herd of stampeding elephants. It swept down to the edge of the ditch and paused at the fiftymile stretch of saltwater between it and the shapeless island still offering the temptation of a foothold in front of the now vastly enlarged Panama Canal. If those engaged in the task, from coordinator-in-chief down to the sweating waterboys, had worked like madmen before, they worked like triple madmen now, for the wind might blow a single seed onto what had been Costa Rica and undo all they had so far accomplished. The explosions were continuous, rocking the diminishing territory with ceaseless earthquakes. After an hour on the job men reeled away, deafened, blinded and shocked. On the South American side, as had been planned, great supercyclone fans were set up to blow back any errant seed. Fed by vast hydroelectric plants in the Colombian highlands, the noise of their revolving blades drowned out the sounds of the explosions for all those nearby. The oceans became interested participants and enormously high tides possibly caused by the difference in level between the Atlantic and Pacific, clawed away great hunks of land. The great island became a small island, the small island an islet. At last nothing but ruffling blue water lay between the Grass and South America. Over this stretch of sea the great fans blew their steady breath, protecting the continent behind from the fate of its northern twin. The passage between was forbidden to all ships for fear they might inadvertently act as carriers of the seed. The lost continent was not only isolated, it was sealed off. From the sharp apex of the inverted triangle to its broad base in the arctic ice the Grass flourished in one undisputed prairie, the sole legatee of all the hopes, trials, afflictions, dreams and victories of the men and women who had lived there since the first alien foot was set upon its soil. FIVE _The South Pacific Sailing Directory_