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.
Average Temperatures in Philadelphia, Pennsylvania, Usa. 1  The annual mean temperature in Philadelphia, Pennsylvania, Usa is quite mild at 12.4 degrees Celsius (54.3 degrees Fahrenheit). 2  The variation of average monthly temperatures is 25.7 C (46.3 F) which is a moderate range.hiladelphia, Pennsylvania Average Temperatures Chart. The average temperature charts use a fixed scale so that you can easily compare temperatures between two or more locations. Simply line up the charts in separate tabs in your browser and toggle between tabs to visualise the differences.