Ford has beaten General Motors for the first time in nearly a century, in terms of number of US factory workers. Ford has 50,703 to GM's 50,300 or so.
Answers. Well, the simplest answer is that the astrolabe pretty well had to be used at night and could not be used in bad weather. The compass, which relys on the magnetic field of the Earth rather than a visualiztion of the stars, works at any time, and in any weather.
Magnetic Fields and Compass Orientation A compass consists of a small, lightweight magnetic needle that is balanced on a pivotal point. The Earth's magnetic field is aligned such that the painted end of the compass needle is always pointing to the north.y clicking on the switch with the mouse cursor to connect the circuit, the conducting wire wrapped around the compass is energized creating a magnetic field that counteracts the effects of the Earth's magnetic field and changes the direction of the compass needle.