Phillips[87] speaks of Holland as being intersected by innumerable canals. “They may,” he says, “be compared in number and in size to our public roads and highways, and as the latter with us are continually full of coaches, chaises, waggons, carts, and horsemen, going to and from the different cities, towns, and villages, so on the former, the Hollanders, in their boats and pleasure barges, their _breckshuyts_ and vessels of burden, are continually journeying and conveying commodities for consumption or exportation, from the interior of the country to the great cities and rivers. An inhabitant of Rotterdam may, by means of these canals, breakfast at Delft or the Hague, dine at Leyden, and sup at Amsterdam, or return home again before night. By them, also, a most prodigious trade is carried on between Holland and every part of France, Flanders, and Germany.” The same author declares that the 400 miles of inland navigation open in Holland in his time, yielded an average income of about 625_l._ per mile, which he declares to be, “almost beyond belief.” What would he have thought had he lived in our time, and seen canals producing an income of 30,000_l._ to 40,000_l._ per mile?[88] _The Haarlem Canal_ was constructed about fifty years ago, for the purpose of draining the _Meer_ or lake of that name. This lake had been formed by an inundation in the end of the sixteenth century, and in the beginning of the eighteenth century it had covered an area of 45,000 acres. Seeing that the lake was gaining upon the land, it was resolved to take effectual means for draining it. This course was precipitated by two furious hurricanes, one in November 1836, which drove the waters of the lake upon the city of Amsterdam, and another in December of the same year, which submerged the lower parts of the city of Leyden. The first step incidental to draining the lake—a work which was undertaken by the Government in 1839—was to dig a canal round about it for the reception of the water, and to accommodate the great traffic which had hitherto been carried on by its means. This canal was made 38 miles in length, 130 feet wide on the west side, and 115 feet on the east side of the lake, and 9 feet deep. All the inlets into the lake, were then closed by large earthen dams; and various works were executed to facilitate the flow of water into the sea. These preliminary works occupied till 1845. To give some idea of the magnitude of the undertaking, it may be mentioned that the area of water enclosed by the canal was rather more than 70 square miles, and the average depth of the lake was 13 feet 1·44 inches. The water had no natural outfall, being below the lowest possible point of sluiceage, and, including rain water, springs, &c., during the time of drainage, it was calculated that probably 1000 million tons would have to be raised by mechanical means. After drainage, too, the site could only be kept dry by mechanical power, so that the annual drainage might amount