Though the original artwork is done by hand (graphite, ink, and paint on paper), reproduction for print or some other kind of mass display method (such as this website) is necessarily a digital process involving scanning hardware and image-manipulation software. The originals are made with this purpose in mind, i.e. to be correctly interpreted and edited during post-production, rather than to be viewed live, in person. This means that the originals might have unsightly pencil marks, inconsistent ink-coverage, painted corrections, notes in the margins, pasted/taped sections, etc., which are not visible in reproduction. (Think of this as being analogous to live action film: wires, motion-capture marks, and blue/green screens may be obvious and necessary on set, but are not meant to be seen by the audience.)
For the sake of this demonstration, the first page of Volume 2 is used, as thoroughly as Charles's records allow.
Because of lacking scanning equipment at the time, and erasing the pencil marks after all of the ink had dried (for cleanliness of scanning), the fully pencil-only version of this page no longer exists in any form. Though having a record of it would be useful for archival purposes, the penciling itself is only a transitory stage between illegible thumbnails and scan-ready ink drawings.