The ornamental design for a tread of a tire, as shown and described.
FIG. 1 is a perspective view of a tread of a tire embodying the new design, it being understood that the tread pattern is repeated throughout the circumference of the tire;
FIG. 2 is an elevational view of the tire tread shown in FIG. 1; and,
FIG. 3 is a radial sectional view of the tire taken on the line 3--3 of FIG. 2.
In the drawings, the broken lines defining the inner bead and sidewall are for illustrative purposes only and form no part of the claimed design. The dark stippled surface shading represents the recessed portion of the tread grooves having depths as best shown in FIG. 3.