They pass through peelers and hit the rotary slicers metal cylinders with sharpened blades around the edges.

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The first 1, 000 Peelers covered a seven-mile circle around Charing Cross and a population of less than 2m and their duties were largely limited to patrols.

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It can identify wine snobs who ski, for Patagonia, or gardeners aged 50-plus who might be in the market for one of Vermont Country Stores' cast-iron apple peelers.

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They still have the original bench at which the founder, Joseph Hudson, made the very first police whistle in the 1880s, replacing wooden rattles that the "peelers" had previously used to sound the alert.

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