The planet Mercury when observed from Earth has a very volatile speed of
movement along the Ecliptic: sometimes it moves at the same speed of the
Sun (apparent speed as observed from Earth), sometimes it moves twice as
fast as the Sun and other times it appears retrograde (moving backward) and
when its motion switches from retrograde to direct or direct to retrograde it
appears stationary for almost one day.
As weird as it may seems nowadays, the changes of speed of the planet
Mercury have a dramatic impact on human affairs including stocks and
commodities market. What sounds weird today once was a key timing
indicators for the ancient astronomers/astrologers.
The first one to observe the importance of observing the speed of Mercury to
catch top and bottoms in the market was George Bayer in 1940, he used
such planetary tools for timing turn dates in the grain market.
As George Bayer discovered, when the apparent speed of Mercury equals
that of the Sun you can expect a turn in a market affected by Mercury.