And this marvellous paragraph from Canby et al. English Composition in Theory and Practice (link):
Quote:
Participles are equally dangerous. Sometimes, as is the case with pronouns, their reference is vague.

Hastening up the steps, the door opened.
On entering'the room, the eye is struck by a huge chandelier.
After eating a hearty dinner, our carriages were brought to the door.
Lost in meditation, the minutes fleeted past.

Each sentence above illustrates what is called the "dangling participle." There is no one word to which the participle definitely refers. In each sentence except the third, they refer presumably to words in a preceding sentence. In the third, the participle refers to the antecedent of our. Errors of this sort are especially common. Participles much be watched; they cannot be trusted without strict surveillance. Make your participles refer to some definite person, thing, or idea. Moreover, see that they refer to some particular person, thing, or idea. Make it clear that they modify one word, and only one; see that they are not ambiguous.
This animus toward the natural and genial aspects of language would be laughable if it were not so frightening.

Ceci n'est pas un seing.