No; there is very little tenacity in brittle substances.
Is there any tenacity in air?
No; because its particles are always trying to separate from each other.
Is there any tenacity in water?
Only a little, just enough to hold its particles together in the form of drops.
Upon what does the strength of substances depend?
Their strength depends upon their tenacity.
Do the different kinds of wood vary much in strength?
Yes; hickory and oak are much stronger than pine or cedar.
When is a knowledge of the strength of wood necessary?