How did Portia address herself to Shylock? Did her praise of mercy have any effect on the Jew?

Portia addressed herself to Shylock as a lawyer and pleaded for him to have mercy on the accused.  She was giving him one last chance to show mercy.  This way, the audience could not feel sympathy for the Jew when his punishment incurred.  We must remember that this is a comedy after all.  Of course, she has no effect on Shylock and he demands his pound of flesh.  He reiterates the initial bond and he wants his revenge.  Of course, this does not happen in the end since he is allowed his pound of flesh, but no blood.