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  precious metals and molding them into the most beautiful coinage known on earth. The assistant assayer, after a last lingering look at his little blue flasks—he was testing the amount of silver in deposits of ore brought in to the Mint from all over the country—if you find any in your back yard the Mint will pay you a dollar an ounce for it—was gracious enough to give me some fleeting glances at the fascinating work going on in the building. The first thing one realizes is the presence of the benign and silent goddess of Science. Those upper floors, where the assayers work in large, quiet chambers, are like the workrooms of some great university, some university happily exempt from the turbulent and irritating presence of students, where the professors are able to lose themselves in the worship of their own researches. Great delicate scales—only you mustn't call them "scales," but "balances"—that tremble like a lover's heart if you lay a hair on one platform, shelter their gossamer workings behind glass cases. My guide showed me one, a fantastic delicacy so sensitive that one feels as clumsy as Gibraltar when one looks at it. Each division on its ivory register indicates one-tenth of a milligram, which, I should say, is about as heavy as the eyelash of a flea. With a pair of calipers he dropped a tiny morsel of paper on one balance and the needle swung over to the extreme end of the scale. With his eyes shining with enthusiasm he showed how, by means of a counterpoise made of a platinum