A man acquires an hourglass which can send him into the future. He asks a pedestrian what year it is and the man replies '71. He assumes 1971 and learns of deposits in the land which make men wealthy and so uses the hourglass to return to the past again and spends all his money buying up the land. He goes into the future again to check his account at the bank and the clerk tells him he is not listed. When he mentions the year the clerk tells him that it is 2071. The man returns to the past and tries to sell off the land, but the previous sellers refuse to buy it back.; A Martian scientist who appears among humans by harnessing the power of lightning bolts finds that his method of travel disturbs people.; A ship directs its own course to the consternation of the sailors aboard and lands at a secluded island to rescue descendants of victims of a mutiny that had occurred aboard her timbers 100 years ago.; A little girl tears up an important letter to her father just to be spiteful after he grounds her. He asks her to tell the truth if she has seen it, and she lies, but her conscience bothers her and she keeps the letter in a box year after year. When she finally tells the truth about the box to her husband he looks in the box and finds money.; Scientists send robots into space for economic means by mining minerals from unexplored planets to fund their experiments. After a few years, they travel to the planet they sent the robots off to and are astonished to find that the robots have greatly developed it. They do not profit, however, as the robots turn the tables on them and put them on a rocket heading back to Earth.; A tourist couple encounter Paul Revere when he comes back to view Battle Green.