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 in boiling nitric acid, which takes out all the silver and leaves only the globule of pure gold. The matter that puzzles the lay observer is, how do you find these things out in the first place? But I would believe anything after one marvel my friend showed me. He picked up a glass that looked like an innocent tumbler of spring water. "This," he said, "is nitrate of silver; in other words, dissolved silver. Don't spill it on your clothes or it will eat them right off your back." I kept off, aghast. Into the tumbler he dropped a little muriatic acid. The mixture boiled and fumed and long streamers of soft, cheesy substance began to hasten toward the bottom of the glass, waving like trees in a gale. "That's the silver," he said, and while I was still tremulous showed me wafers of gold dissolving in aqua regia. When completely dissolved the liquid looks like a thin but very sweet molasses. He then performed similar magic upon some silver solution by unloading a pipette of salt water on it and shaking it in a little machine called an "agitator." After which he felt I was sufficiently humble to show me the furnace room.

If you have an affection for the nice old silver cartwheel dollars, keep away from the furnace room of the Mint, for one of the first things you will see is whole truckloads of them moving silently to their doom. I was told that there is a shortage of silver in Europe these days, particularly since troubles in Mexico have reduced that country's