What does the word “tempest” mean , as used in paragraph 74?

What is in his westrose president lincoln central claim in the speech

Highlight all instances of parallel structure. there is no longer any room for hope. if we wish to be free—if we mean to preserve inviolate those inestimable privileges for which we have been so long contending—if we mean not basely to abandon the noble struggle in which we have been so long engaged, and which we have pledged ourselves never to abandon until the glorious object of our contest shall be obtained—we must fight!

What are the similarities of physical and chemical change ?