The ornamental design for an easel, substantially as shown and described.
FIG. 1 is a perspective top view of the easel comprising a new, original and ornamental design. In all drawings, the elements shown by dashed lines are not claimed;
FIG. 2 is a left side view of the easel comprising the new, original and ornamental design;
FIG. 3 is a right side view comprising the new, original and ornamental design;
FIG. 4 is a rear view of the easel comprising the new, original and ornamental design;
FIG. 5 is a front view of the easel comprising the new, original and ornamental design;
FIG. 6 is a top view of the easel comprising the new, original and ornamental design; and,
FIG. 7 is a bottom view of the easel comprising the new, original and ornamental design.
The ornamental design is for an easel for use by artists.