Da Vinci's Rule of the Trees

“Da Vinci’s Rule of the Trees” (“all branches of a tree … put together are equal in thickness to its trunk.”) appears to be true.

Da Vinci wrote in his notebook that "all the branches of a tree at every stage of its height when put together are equal in thickness to the trunk." In other words, if a tree’s branches were folded upward and squeezed together, the tree would look like one big trunk with the same thickness from top to bottom.
 

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