Thursday, July 18, 2019
Beautiful article on magnetic senses
A lively article at Aeon gives the full history of research on the human magnetic sense, includes lots of studies I hadn't heard about, and emphasizes the role of declination or dip in animal magnetic senses.
There are only two odd errors, which don't affect the main theme. Both could have been eliminated if the author had called on an engineer type to proofread the article. Hint, hint.
Odd error 1:
Our planet is an enormous magnet, an object whose internal electrical charge causes it to be positive at one end and negative at the other.Magnetism isn't caused by an internal electrical charge. The earth doesn't have a major planet-scale electric charge. It has an infinite number of constantly changing tiny electric charges, since every single living cell and plant and animal uses electric charges for internal and external communication. The magnetic field happened because the core of the earth is iron spinning inside the sun's magnetic field. We don't know why the sun has a magnetic field. God knows. Odd error 2:
During the years that Baker ran the Manchester experiments, AM radio broadcasts were common throughout the US, where replication attempts were most frequent, but nearly nonexistent in the UK. If humans, like pigeons, use a mechanism for magnetoreception that can be jammed by AM frequencies, it explains why so much time and effort put into replicating Baker’s finding ended in failure.Nonsense. British radio stations have used SW more than American stations, but British stations always used the BCB heavily. A quickly found specific reference from the '70s:
23 November 1978 – Radio 1 moves from 247m (1214 kHz) to 275 & 285m (1053 & 1089 kHz) medium wave as part of a plan to improve national AM reception, and to conform with the Geneva Frequency Plan of 1975.I can't figure out where the author got this "fact". Even if Britain hadn't been using MW, the effects of SW would be identical. There must be a difference between the two nations, but broadcasting ain't it. How about overhead powerlines vs underground powerlines? Most of the city-scale wiring in Britain is underground, while most in US is on poles. Was this already true in the '70s? I can't find a verbal indication from a quick online search. These pics of Manchester in the '70s show streetlights on poles but no overhead wires at all.
Labels: Grand Blueprint
¶ 7:47 AM
