magnetic needle

After analyzing the field strength frozen in the tiny magnetic needles, they found that its intensity had already jumped to 70% of present values, they reported at the AGU meeting.

The researchers looked at samples of plagioclase and clinopyroxene from eastern Quebec, Canada and found that they contain magnetic needles approximately 50 to 100 nanometers in size, surprising the researchers.

Finding the magnetoreceptors responsible for triggering these neurons has been like looking for a magnetic needle in a haystack.

On this as on the previous voyage, Hudson made some observations on the inclination or “dip” of the magnetic needle, and he is probably the first Englishman who had done so.

Faraday showed that a rotating disk of non-magnetic metal would draw after it in similar rotation a magnetic needle suspended over it, and even a heavy magnet.