How did Voltaire use irony to insult Rousseau?

Voltaire did not use irony to insult Rousseau, but rather outright attacks and personal insults. His criticisms were direct and often scathing, focusing on Rousseau's character and behavior rather than on his ideas. For example, Voltaire referred to Rousseau as a "madman" and a "charlatan," and belittled his achievements by mockingly calling him "the great Jean Jacques."