Tick, tap, tap-tap, ticker-ticker-tapper-tapper; tick-teck, tacker-tap went a typewriting machine, and scratch-scratch went two pens, in one of the minor offices connected with that vast wealth-producing industry known as the De Beers Diamond-Mines, where, seated at desk and table, three young men were hard at work, one manipulating the typewriter, one writing a letter, and the third making entries in a fat leather-covered book with broad bands and a big letter distinguishing it upon the back.