The ornamental design for a blower, as shown and described.
FIG. 1 is a perspective view of the front, bottom and right side of a blower showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a left side view thereof;
FIG. 8 is a perspective view of the top, rear and right side thereof; and,
FIG. 9 is a perspective view of the usage thereof.
The broken line showing of portions of the blower is included for the purpose of illustrating environmental structure and forms no part of the claimed design.