If you're looking for a quote regarding using sunlight as a source or energy, a quote by Maria Telkes would be '"Sunlight will be used as a source of energy sooner or later..." she said. "Why wait?"'
It is intended to increase immunity against that antigen back to protective levels, after memory against that antigen has declined through time.
When the soil is dry, it wouldn't be easy to make a footprint so the soil must be moist. Later, the print would harden and that preserves the footprint.
Overall: soil is moist.
Im pretty sure its volcanoes. Japan has over 100 active volcanoes
