the lighthouse was nearing completion, a set of dwellings were constructed on St Mary's to accommodate keepers' families (and the keepers themselves when they were not on station). The light at the time was manned by a team of four: at any one time, three would be on station in the lighthouse, and the fourth on leave on St Mary's. Exposed to the elements Faced with the full force of the Atlantic, Walker's lighthouse proved vulnerable: in heavy weather the tower regularly shook, the vibrations being powerful enough to cause objects to fall from shelves, and even causing the optical apparatus to fracture. The lighthouse had initially been provided with a fog bell; however this was washed away during a storm in January1860. (It was replaced with a larger bell, but not until 1864; the bell was sounded once every ten seconds). Over the years that followed various expediencies were tried to mitigate the effects of heavy weather upon the lighthouse. During an especially heavy storm in April 1874 the tower was severely and repeatedly shaken by a succession of waves, which shattered the reinforced glass of the lantern and sent cascades of water down through the living quarters. Later that year James Douglass (who had succeeded Walker as Engineer-in-chief at Trinity House) returned to Bishop Rock with a team of men to reinforce the lower section of the tower using broad iron bands, which were bolted through the stonework. In the winter of 1881 a further series of storms battered the lighthouse, wrenching sizeable blocks of granite away from the structure just above the high water mark. James Douglass was again sent to inspect the tower and he reported that its structural safety had been seriously affected. He began drawing up designs to reinforce the structure by laying massive granite blocks into the rock and dove-tailing them onto the lighthouse. Douglass's 'strengthening and improvement' Ultimately, Douglass's plan of renovation for the lighthouse would amount to a near complete rebuilding: it involved fully encasing Walker's tower within new external courses of granite, then removing the old lantern storey and existing internal floors before increasing the strengthened tower's height by a further . At the same time, he sought to diminish the impact of waves upon the tower by making the base section cylindrical, rather than conical. The work began in 1883 under the supervision of Sir James's eldest surviving son,