showing between them is decomposed: a blade of blue or violet light, inexpressibly thin and of the width of the cylinders, passes through the entire distance. As for the "chilling" of iron, it was applied first to wheels in Baltimore, in 1833, by Mr. Ross Winans; and then, during the same year, Mr. Bonney and his nephew, George G. Lobdell, established the business we see, which has gradually grown to its present capacity of three hundred wheels per day. [Illustration: FOUNTAIN.] [Illustration: "IN MEMORY OF THE SOLDIERS AND SAILORS OF DELAWARE WHO FELL IN THE STRUGGLE FOR THE UNION."] The use of such cylinders as we have just seen under the difficult process of polishing is only understood when we explore some large paper-mill, where they take the place of the old-fashioned frame of wire gauze which produced the hand-made paper. We may select the splendid works of Messrs. Jessup & Moore on the Brandywine. Our welcome is sure to be a cordial one, for among the largest customers of the firm are the publishers of _Lippincott's Magazine_. The process of paper-making by the Fourdrinier machine was so fully explained in our Number for last November that it is useless now to repeat the details. But it would never do to leave the Brandywine without a glance at least at one of its principal manufactures. The mill of Jessup & Moore uses the strength of the torrent as an auxiliary to its steam-power of seven hundred and fifty horses. The machinery is made by Pusey, Jones & Co., whose iron ships and machine-shops we have already examined: the rolls of admirable accuracy are from the shops of J. Morton Poole & Co. The paper-making process--the vast revolving boiler of twelve feet by twenty-six; the countless sacks of filthy rags, that have clothed peasants of the Black Forest, beggars on the steps of St. Peter's and Egyptian fellahs; their reduction to purity, and hardening from pulp to snowy continuities of endless, marginless paper,--all this is of rare interest in the watching, but has been told until the public is satiated. We leave the banks of the Brandywine and the wharves of Christine, and try to lose ourselves in the thickly-built heart of the city. Even here the implacable business spirit exhibits itself at every turn. In place of the placid millers and quaint refugees of the last century at their doors, we see the shops, the storehouses of manufacturers' supplies, the hotel and the theatre; and, pervading all, the vast throng of artisans, providing such problems of local government and education as the last century never dreamed of. [Illustration: HIGH-SCHOOL.]