252											26
                                                                      
                                                                      	Base of shafts.  We have seen that the mechanical
                                                                      conditions require none - or a mere square block.  But
                                                                                    There are from distinct sides in volved in our perceptive
                                                                      of the agreeableness of bases;
                                                                      1.  That of a Socket for the shaft, to keep it from slip-
                                                                      ping, requiring merely a ring round it;
                                                                      2nd.  The Props on the four sides, or spurs: thrown out
                                                                      very early from this ring to the angles of the square
                                                                      base as in St Ambrozio.
                                                                      3rd.  A raising of the ground beneath so as to provide
                                                                      against the depression caused by weight of building;
                                                                      4th.  An aesthetic requirements:  The rounding of the
                                                                      awkwardly angle at the base of shafts;  if this be not
                                                                      eough done by the ring or socket; one may look on a com-
                                                                      mon base moulding as on a kind of beading at the edge of
                                                                      a square moulding;  a buckling of the vacant instead of
                                                                      the solid angle;  Only note that this levelling is wrong if
                                                                      it gives any idea of the dispersion of lines of pressure
                                                                      In the capital, there may be a meeting of radiant lines
                                                                      from above   but in the base there can be but one line of
                                                                      pressure, a vertical through centre, any lines which seem
                                                                      to suggest any other, as of a capital recessed, are false
                                                                      and wrong.

[Version 0.05: May 2008]