The phrase “happy as a sandboy” is well known, although not so much these days as in times gone past. The modern phrase is more likely to be “chuff to little bits”. Either way it means that someone is very pleased and showing it.
In early Victorian times loose dry sand was in demand to be spread on floors, then mostly bare boards, to absorb any liquid spillage and so enable the floors to be swept more easily. Collecting and distributing the sand was done by “boys” (of any age) and it provided them with a living. They carried bags of the stuff around and sold it as required. It was particularly in demand for the floors of inns and hostelries. As may be expected these “boys” worked up a thirst in the course of their labours and, not surprisingly were often paid by a landlord, at least in part, with ale. Consequently they were usually half-cut (merry or jolly). Hence the origin of the phrase.
Charles Dickens was aware of the practice. He visited Bristol as a newspaper reporter in 1835 and there is a theory that he learned the phrase during his time here. In “The Old Curiosity Shop” (1840) he includes an inn called the Jolly Sandboys that displayed a sign outside depicting three drunken sandboys. Redcliffe caves had been a source of sand over many centuries and it is suggested that the phrase actually arose to describe those “boys” extracting sand from the caves and selling it to the adjacent Ostrich Inn in exchange for ale. A bit far-fetched maybe but “happy as a sandboy” had to start somewhere.