O, it is monstrous, monstrous:
Methought the billows spoke and told me of it;
The winds did sing it to me, and the thunder,
That deep and dreadful organ-pipe, pronounced
The name of Prosper: it did bass my trespass.
– William Shakespeare
The Tempest, Act 3, Scene 3. Alonso says this in response to the frightening shapes and sounds created by the spirit Ariel, who appeared as a terrifying harpy. Alonso uses a metaphor compares the thunder he heard to the deep and dreadful sound of an organ-pipe. This passage is an example of dramatic irony, as the audience is already in on the act and knows that Ariel was commanded by Prospero to perform his terrifying act to scare away his master’s adverseries. The audience can actually see Prospero watching and Ariel overseeing the whole show. Alonso’s use and repetition of the word "monstrous" to describe what is going on suggests that the conjuror Prospero may himself be monstrous.