What contrast is there between Eric's response to his fathers account and Geralds response?

I'm not exactly sure where in act one you mean but as the Inspector surmises, Birling has now remembered Eva Smith: she was discharged from her employment at his works at the end of September in 1910. Gerald attempts to leave, sensing the potential for embarrassment, but when Birling introduces him to the Inspector, the Inspector gravely says he would prefer that Gerald stay. Birling, “somewhat impatiently,” tells the Inspector that there is nothing “mysterious” or “scandalous” about this business, since it happened more than eighteen months ago, and therefore it can have nothing to do with this girl’s suicide.