India, May 6 -- So omnipresent on Delhi's summertime roadsides, the refrigerated cold water trolley doesn't trade only in refrigerated cold water. The cart vendor also keeps dozens of yellow-green lemons, which he employs to spike up the flavour of his bottled banta drink. That said, some vendors do condescend to serve simple shikanji on request, squeezing lemon into a glass of cold water, stirring in with a pinch of black salt.

Delhi's traditional shikanji cart, however, is an altogether different apparatus, in which the ice of the shikanji is prepared manually. This demands strenuous physical labour. Such an old-fashioned "shikanji machine" is made of a cylindrical vessel usually wrapped in a red cloth (the red is to instantly catch a ...