Why did Judge Ford cup her hand over the receiver when Mr how brought the appetizers in the Wasting Game?

In "The Westing Game," Judge Ford cups her hand over the receiver to keep her conversation private while discussing important matters related to the Westing estate. This gesture indicates her desire to maintain confidentiality, as she is aware that others may be listening in on her phone call. It reflects her cautious and strategic nature, which is essential in navigating the complexities of the game and the various characters involved.