In one embodiment, components within different hierarchical document levels of a document have individual access rights and various hierarchical relationships with other components on different hierarchical levels within the document. For improving the applicability of the machining apparatus, this machining apparatus according to the invention is characterized by a workpiece-holding table that is designed such that it bridges the workpiece support and can thus be firmly attached to the frame. For example, a first memory cell can have a first control gate on the first side of the conductive pillar and a first charge trap interposed between the first side of the conductive pillar and the first control gate. A tool bit holder securely holds and drives reduced thickness tool bits that can also be engaged in and driven by conventional sockets having a regular hexagonal shape. Any cracks emanating from the rock chip tend to remain confined within the circular crack barrier. Strong base Type 1 ion exchange resin is used to remove acid from the solution resulting in a treated solution that contains only a small amount the original acid but all of the dissolved salts.