I intended to concentrate throughout the summer on matters of extreme urgency: ocean waves breaking in the sunlight and swirls inside oyster shells and the mystery of the sound of ice hitting the sides of a glass. In the afternoon, the ice makes only this gentle, clicking, almost tinkling sound. Yet at night it sounds like gravel being poured into a barrel. Why is ice louder at night than it is in the daytime? Let me put on my shoes and we’ll go out and investigate.