The most interesting place connected with the machinery of the Bank of England is the Weighing-Office, which was established about 1840. In consequence of a proclamation concerning the gold circulation, it became very desirable to obtain the most minute accuracy, as coins of different weight were plentifully offered. Many complaints were made, that sovereigns which had been issued from one office were refused at another; and though these assertions were not, perhaps, always founded on truth, yet it is indisputable that the evil occasionally occurred. Every effort was made by the Directors to remedy this, some millions of sovereigns being weighed separately, and the light coins divided from those which were full weight. Fortunately, the Governor for the time being, (Mr. W. Cotton), before whom the complaints principally came, was attached to scientific pursuits; and he at once turned his attention to discover the causes which operated to prevent the attainment of a just weight. In this he was successful, and the result of his inquiry was, a machine, remarkable for an almost elegant simplicity. About 80 or 100 light and heavy sovereigns are placed indiscriminately in a round tube; as they descend on the machinery beneath, those which are light receive a slight touch, which moves them into their proper receptacle; while those which are the legitimate weight, pass into their appointed place. The light coins are then defaced by a sovereign-cutting machine, remarkable alike for its accuracy and rapidity. By this, 200 may be defaced in one minute; and, by the weighing machinery, 35,000 may be weighed in one day.

An eminent member of the Royal Society mentioned to the writer, that, amongst scientific men, it is a question whether the Weighing-Machine of Mr. Cotton is not the finest thing in Mechanics; and that there is only one other invention—the envelope-machine of De la Rue—to be named with it.—Francis's History of the Bank of England.