§ XX. We have hitherto supposed that all grouped or clustered shafts have been the result or the expression of an actual gathering and binding together of detached shafts. This is not, however, always so: for some clustered shafts are little more than solid piers channelled on the surface, and their form appears to be merely the development of some longitudinal furrowing or striation on the original single shaft. That clustering or striation, whichever we choose to call it, is in this case a decorative feature, and to be considered under the head of decoration. § XXI. It must be evident to the reader at a glance, that the real serviceableness of any of these grouped arrangements must depend upon the relative shortness of the shafts, and that, when the whole pier is so lofty that its minor members become mere reeds or rods of stone, those minor members can no longer be charged with any considerable weight. And the fact is, that in the most complicated Gothic arrangements, when the pier is tall and its satellites stand clear of it, no real work is given them to do, and they might all be removed without endangering the building. They are merely the _expression_ of a great consistent system, and are in architecture what is often found in animal anatomy,--a bone, or process of a bone, useless, under the ordained circumstances of its life, to the particular animal in which it is found, and slightly developed, but yet distinctly existent, and representing, for the sake of absolute consistency, the same bone in its appointed, and generally useful, place, either in skeletons of all animals, or in the genus to which the animal itself belongs. § XXII. Farther: as it is not easy to obtain pieces of stone long enough for these supplementary shafts (especially as it is always unsafe to lay a stratified stone with its beds upright) they have been frequently composed of two or more short shafts set upon each other, and to conceal the unsightly junction, a flat stone has been interposed, carved into certain mouldings, which have the appearance of a ring on the shaft. Now observe: the whole pier was the gathering of the whole wall, the base gathers into base, the veil into the shaft, and the string courses of the veil gather into these rings; and when this is clearly expressed, and the rings do indeed correspond with the string courses of the wall veil, they are perfectly admissible and even beautiful; but otherwise, and occurring, as they do in the shafts of Westminster, in the middle of continuous lines, they are but sorry make-shifts, and of late since gas has been invented, have become especially offensive from their unlucky resemblance to the joints of gas-pipes, or common water-pipes. There are two leaden ones, for instance, on the left hand as one enters the abbey at Poet's Corner, with their solderings and funnels looking exactly like rings and capitals, and most disrespectfully mimicking the shafts of the abbey, inside.