The accompanying illustration will afford an idea of the manner in which this difficult engineering problem was solved. By means of a series of openings made in the base of the tower, as above described, the latter was raised on a solid platform of oaken planks; while it was surrounded from base to summit by a framework of stays or props, strengthened by cross beams. The platform rested on one hundred and forty-four cast-iron wheels, grooved like those of a locomotive, and running on eight parallel rails, likewise of cast-iron, which, with their “sleepers,” were laid along the masonry of the pier and jetty. When the mass had moved a few feet, the rails were lifted, and laid down again in front of the machinery, and this process was repeated until the new site of the lighthouse was reached. Iron chains attached to the platform were wound upon windlasses, worked by a band of sturdy labourers. The various stages of the operation were accomplished in thirteen hours and twenty-four minutes. The combined efforts of forty men were required for five hours to carry the apparatus over the 28 feet of the first section, while eighteen men sufficed to carry it in eight hours and twenty-four minutes over the 447 feet of the second. In this latter part the rails were at first laid down on a curve, so as to bring the pharos into a symmetrical position with the jetty, then it advanced parallel to itself, following a slightly inclined plane. It was prevented by wedges from deviating during this ascent from a perpendicular line. The object of this twofold disposition was to veer the pharos round, and to raise it to a higher level—which, as we have seen, was an indispensable condition. The removal was eventually accomplished with so much success, and so little interruption to the business of the harbour, that the lamp was lighted in the evening at the usual hour. [Illustration] [Illustration: TRANSPORTING A LIGHTHOUSE—SUNDERLAND.] [Illustration] CHAPTER VI. LIGHTHOUSES ON THE ENGLISH COAST. We propose, in the present chapter, to glance at a few of the best known pharoses which illuminate our home-waters, but without observing any particular order. Our description of each will be brief, for it is needless to say that, as a rule, lighthouses closely resemble one another in their principles of construction as in their general arrangements, and that the differences between them are simply matters of detail. * * * * *