trunk

Why are cylindrical trunks?
Geometry tells us that the area of a circle is larger than any other.
Trees can become a clean energy source
According to NewScientist, plugging the electrode plate into the trunk to obtain electric current seems to be an unbelievable thing ...
The mystery of the giant tree trunk stands in the middle of the lake for 100 years
The mysterious trunk was discovered on Lake Crater for the first time in 1902, with an elevation of about 9.1m, rising from the water surface about 1.2m.