St. Mark's does not have minarets, which are tall usually slender towers or turrets connected with mosques in Islamic architecture, and which date from the eighth century. Ruskin uses the term loosely and presumably refers to a combination of St. Mark's five thirteenth-century onion domes, capped by Byzantine lanterns, and to its proliferation of fifteenth-century canopied niches, ogee arches and crocketted pinnacles with their sometimes gilded decoration. In his Introduction to the second volume of The Stones of Venice (1853), Ruskin speaks of approaching the building from the 'Bocca Di Piazza' under the Ala Napoleonica to confront 'a multitude of pillars and white domes, clustered into a long low pyramid of coloured light; a treasure-heap, it seems, partly of gold' ( Works, 10.82). Ruskin would appear to be referring in Modern Painters to Gentile Bellini 's Procession in Piazza San Marco. This was originally from the Scuola di San Giovanni Evangelista and is one of a series by various artists representing incidents from the story of a relic of the True Cross still housed there. It is now in the Accademia.