chop off the morter joint that is left on your cap and the top course of the pillar in question then using a 4 to 1 sand cement mortar bed the stone back on, if in any doubt about its sticking power, make a cement slurry using clean water and cement powder, add the cement to the water not the other way around or you will end up mixing the worlds supply of gruot dont mix more than a pint of water, then carefully paint both surfaces with this mix, the mix should be of single cream consistancy, then spread your mortar bed half inch deep plonk on the cap measuring for centreing, leave it for a couple of days and bobs your uncle.
john, January 2008
