In this unusual and informative book, the main character is an air mass—cP—born in the Northwest, in the cold, dry cradle between the Canadian Rockies and the moist barrier of Hudson Bay. Eric Sloane, illuminating his chronicle with his own superb drawings, describes the eventful journey of this air mass, showing how it affects the lives of many of the people it encounters.

The voyage of cP from north and west to south and east is no ordinary journey, nor is Mr. Sloane's a commonplace view of weather at work. He sees that the sky begins where the earth and the seas leave off, that man dwells within the sky, not beneath it, and that his fate in inextricably bound up with what occurs there.

From the dust jacket