The ornamental design for a grandfatherclock, substantially as shown and described.
FIG. 1 is a left front perspective view of a grandfather clock showing my
new design;
FIG. 2 is a right side elevational view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a left front perspective view thereof with the door opened and
the clock works omitted for ease of illustration of the mirrored rear wall
of the clock casing.