A chambered doctor blade apparatus provides an automatic system for cleanup and replacement of coating substance, as well as operating a hydraulic head loading system that includes hydrostatic compensation, and integrates the head loading mechanism into the automated cleaning, flushing and replacement cycle. For some embodiments, a current-guiding structure may be provided including adjacent high and low contact areas. When an HDA verb is received by the codec, the codec determines whether the verb is associated with one of the overriding responses. The imaging section obtains scan data read from the original document by light irradiated to the original document from the light source. The gemstone’s girdle has eight left top half facets and eight right top half facets, and eight left bottom half facets and eight right bottom half facets.