Sliding clamp for easels
FIG. 1 is an isometric view of the clamp embodying my ornamental design; 
     FIG. 2 is an elevation view of the left side of the clamp of FIG. 1; 
     FIG. 3 is a front elevation view of the clamp of FIG. 1; 
     FIG. 4 is an elevation view of the right side of the clamp of FIG. 1; 
     FIG. 5 is a rear elevation view of the clamp of FIG. 1; 
     FIG. 6 is a top view of the clamp of FIG. 1, and 
     FIG. 7 is a bottom view of the clamp of FIG. 1.