Finger bowl

[2]: 208–209 After dessert (or after the fruit, if that forms the last course), guests lightly dip their fingertips into the water, one hand at a time, and then wipe them on the napkin in their lap.

[4]: 435 In high-end American restaurants of the early to mid-20th century, finger bowls were presented at the end of the meal.

[5] In some styles of informal and restaurant service and at very large gatherings, the dessert fork and spoon are set above the top edge of the plate at the start of the meal (a practice considered incorrect at dinner parties).

This innovation, possibly resulting from ignorance of correct usage, is of unknown and apparently recent origin.

Before that, "live music and finger bowls were two amenities put forward as competitive attractions over places that didn't have them."