Breakfast was served from 7:30-9; Dinner from 12:30-2; Supper from 6-7:30. Sunday breakfast was served from 8-9:30.
What is interesting about this menu and the one that follows is that the major meal of the day is being served in the middle, rather than at the end, of the day. In fact, as the twentieth century progressed, "the meal known as dinner was moved later and later in the day and came to be eaten at night, replacing the light meal called supper." - Wikipedia
Dinner menu, dated August 26, 1904
An even earlier, Lakeside House supper menu, dated August 19, 1900. Notice how much simpler this menu is then the dinner menus, seen above.