I am a bit confused by this part.

The exhalations whizzing in the air
Give so much light that I may read by them.
(opens the letter and reads)
“Brutus, thou sleep'st. Awake, and see thyself.
Shall Rome, etc. Speak, strike, redress!”
“Brutus, thou sleep'st. Awake.”
Such instigations have been often dropped
Where I have took them up.
—“Shall Rome, etc.” Thus must I piece it out:
“Shall Rome stand under one man's awe?” What, Rome?
My ancestors did from the streets of Rome
The Tarquin drive when he was called a king.
—“Speak, strike, redress!” Am I entreated
To speak and strike? O Rome, I make thee promise,
If the redress will follow, thou receivest
Thy full petition at the hand of Brutus!

Is Brutus actually speaking in this or is he reading the letters aloud?

I thought that most of these were letters but the one part Brutus said was :

To speak and strike? O Rome, I make thee promise,
If the redress will follow, thou receivest
Thy full petition at the hand of Brutus!

Is the part above part of the letters or is it said by Brutus??

Thank you for using the Jiskha Homework Help Forum. When it comes to literature, be sure to always give the title, author and section. Here are 2 sites to help you research your question:

http://www.sparknotes.com/shakespeare/juliuscaesar/section1.html

http://www.cliffsnotes.com/WileyCDA/LitNote/id-43.html

Shakespeare frequently had characters speak in monologues ( http://www.google.com/search?q=shakespeare+monologues&rls=com.microsoft:en-us:IE-SearchBox&ie=UTF-8&oe=UTF-8&sourceid=ie7 ) or read letters as methods for letting the audience in on background or private thoughts or other elements not able to be conveyed by actions and dialogue.

=)

In the given passage, Brutus is actually speaking in the lines that you have mentioned:

"To speak and strike? O Rome, I make thee promise,
If the redress will follow, thou receivest
Thy full petition at the hand of Brutus!"

These lines are spoken by Brutus himself and not read from the letters. This can be inferred from the fact that Brutus is responding directly to the content of the letters he has read, contemplating the message and making a promise to Rome in response.

It is important to note that throughout the play, Shakespeare often uses monologues and soliloquies as a way for characters to express their inner thoughts and feelings directly to the audience. This technique allows the audience to understand the character's motivations, conflicts, and decisions more deeply. In this case, Brutus's monologue reveals his internal struggle, his sense of duty to Rome, and his resolve to take action.

To clarify the context of the passage, it would be helpful to know the title, author, and specific scene from which this excerpt is taken. This information can assist in further analysis and understanding of the character and the play.