The whistle of the steamer saluted three times—twice short and once long—the sun which rose over the deep green mountains of Costa Rica. The signal was answered in due time. A small tug put off from the long iron pier. There was a launch at the end of its tow line, a big, flat scow of a lighter. It came out across the smooth mother-of-pearl stretch of water, jerking and bobbing over the great Pacific swells. The tug shot by the steamer, the launch threw loose the tow line, and as it came alongside the forward…