What does Chillingworth do when he sees Dimmesdale's tranformation?

I'm going to assume that you are referring to chapter 23 when a much stronger and resolute Dimmesdale climbs the scaffolds to ask Hester and Pearl to join him. We can infer that Chillingworth is pretty panicked. Chillingworth attempts to stop him. Acting as his "physician", he warns Dimmesdale not to go. It is too late though, Chillingwoth has lost his hold over the minister. Finally Dimesdale has found the courage to do what he should have long before and perhaps a little redemption.