Answer:
Antithesis
Step-by-step explanation:
Antithesis is a rhetorical device in which two opposite ideas are put together to create a contrast. It is usually accompanied by parallelism - the use of similar or identical grammatical structures in clauses or sentences to create rhythm or emphasis.
Here, we have two ideas. They are separated by a semicolon.
- By perseverance and fortitude we have the prospect of a glorious issue;
- by cowardice and submission, (we have) the sad choice of a variety of evils...
It's clear that these two ideas are completely different. Perseverance and fortitude and cowardice and submission, which are opposites, lead to opposite results. This is why this is an example of antithesis. It is also accompanied by parallelism. A prepositional phrase with the preposition by and the conjunction and is repeated in both clauses.