What are some examples of ethos, logos, and pathos in Patrick Henry's Speech to the Virginia Convention?

Ethos is argument from the character of the speaker. It can be of two types, intrinsic, meaning created within the context of the speech itself, and extrinsic, or existing independent of or prior to the speech. For extrinsic ethos, Henry was a well educated lawyer who had served in House of Burgesses and had a solid track record of pushing back against British rule. His intrinsic ethos appears at the start of the speech, where he affirms his patriotism and argues that his actions are motivated precisely by loyalty rather than disloyalty.

Argument from logos implies reference to logic rather than simple citation of facts. It is a method of emphasizing the abstract principles of reasoning such as the rules of inference. A typical example of this is:

... in proportion to the magnitude of the subject ought to be the freedom of the debate ...

This is an argument from analogy, following what in ancient rhetoric was termed the topos of greater and lesser, which is considered by Aristotle to be among the common topics of both forensic and deliberative oratory. 

The peroration, with its use of highly charged emotional language and vivid imagery, is an example of pathetic argument which attempts to sway the emotions of its hearers.