The expression "of the sand flows" appeared due to the male fashion 16th century. And may applies exclusively to men. 477 years ago, April 10, 1536, during the visit of England, the Duke of Fabrizio Bologna struck the King Henry VIII and Queen Anna Bolein the size and design of his Gulfi. King Heinrich VIII liked this item, and he adopted her for himself.
Initially, Gulfik was created to cover the genitals. But gradually turned into a fashionable detail. At the beginning of the 16th century, Gulfik grew up in size, became more and decorative, visually increasing the size of the genital organs. Gulfiki sewed from such expensive fabrics as velvet and silk, were expanded by gold threads and decorated with pearls, embroidery, ribbons, precious stones.
Some gulfiki were directed up. To maintain such a "standing" form, the fabric was duplicated and laid, most often in a few layers. To create an impression about a more impressive size of your dignity and look more attractive for the opposite sex, some men even used gulfiki as a kind of pocket, hiding there are small valuables and money. And the weight of the wallet and the density of packing coins was very eloquently talked about the male advantages of the cavalier. Hulfik now emphasized them, and did not hide.
Men are victory, who did not have enough jewels and money, laid themselves in the gulfik bags with hay, sawdust, horse hair, grass and sand. But the sand occupied the leading place and was the most preferred material for giving Gulfi. And so, it happened, during the dance with the lady, or, worse, the solemn reception (on which not to hide in the crowd of dancing) the bag could suddenly scratch, and the sand from it began to roam on the floor. Following such a poor thing, the phrase sounded: "From it, the sand is already lifted, and he can't calm down."
a source