The magnetic compass is an old Chinese invention, probably first made in China during the Qin dynasty (221-206 B.C.). Chinese fortune tellers used lodestones (a mineral composed of an iron oxide which aligns itself in a north-south direction) to construct their fortune telling boards.
Guide to Pennsylvania weather in April. The average maximum daytime temperature in Pennsylvania in April is a comfortable 17Â°C (63Â°F). The average night-time temperature is usually a cold 5Â°C (41Â°F). There are usually 7 hours of bright sunshine each day, which represents 55% of the 13 hours of daylight. Expect 95mm (3.7 inches) of rainfall across the whole of April with 11 days with some rain falling.
In Philadelphia, the summers are warm and humid, the winters are very cold, and it is wet and partly cloudy year round. Over the course of the year, the temperature typically varies from 26Â°F to 87Â°F and is rarely below 13Â°F or above 94Â°F.