robots whose functions were manifold , sparked , placed extraneous parts , numerous extensions on the gleaming tiled floor and set about the business of buffing and polishing and wiping and shining and tidying each other and the bewildered customers while whistling in a variety of distinguishing notes a variety ( depending on their country of origin ) of patriotic songs from days of old , of historic mechanical sobriety , when , sherzo recalled , having been there , countries and patriotism still found their way up onto the dusty blackboard .