"In spite of all my efforts to reform the practices of the Mint, and to make each newly coined guinea identical to the last, some variation in weights persists. Some guineas are slightly heavier than others. Such errors are reducible but not eradicable. I have reduced them to the degree that, where honest persons are concerned, no variation exists. That is, most men in London—and I include sophisticated men of commerce—would trade one guinea for another without hesitation, and certainly without bothering to take out a scale and weigh them."