Processing cassette
FIG. 1 is a perspective view of the processing cassette with its halves folded over one another; 
     FIG. 2 is an elevational view of the processing cassette with its halves unfolded and showing their outer faces; 
     FIG. 3 is a side view of the unfolded processing cassette, as seen from the left of FIG. 2; 
     FIG. 4 and 5 are respectively bottom and top views of the cassette with its halves folded over as in FIG. 1. 
     FIG. 6 is an elevational view of the processing cassette with its halves unfolded, as in FIG. 2, but showing their inner faces; and, 
     FIG. 7 is a vertical sectional view of the processing cassette, as seen along broken lines VII--VII of FIG. 6.