_The Chain at Chatham._--When, early in the seventeenth century, Chatham had grown to considerable importance as a naval centre, a curious method of defence was devised. A long and stout iron chain was placed across the Medway at the western end of Gillingham Reach, near Upnor Castle, with the idea of effectually stopping the progress of alien ships up the river beyond this point. When the chain was originally placed here is not exactly known, but it was repaired in 1606, and soon after abandoned. In 1623 the chain was superseded by a boom made up of masts, iron, and cordage. A few years later, in 1635, either a new boom or a new chain was placed across Gillingham Reach. The chain came into great prominence when the Dutch invaded the Thames estuary and the Medway in 1667. It was fixed up at Gillingham either on 27 April or soon afterwards. The published accounts are not quite clear or consistent. The claws for fastening and heaving it up were expected to arrive but apparently were not forthcoming on the date mentioned. Although there had been a great chain here before it does not appear to have been stretched properly across the river. This was now attended to under the direction of the Duke of Albemarle, who went down to Chatham posthaste to complete the defensive works. The chain, consisting of links made of iron bars, six inches in circumference, was strained probably in such a way that it would not be visible above water, and it was perhaps buoyed at intervals. A small battery of guns was placed on shore at each end of the chain in order to protect it from injury by the Dutch. The _Unity_, a warship, was stationed to the east of the chain, whilst on the west side a Dutch prize was sunk, and several ships were on guard. The Dutch ships, which had been observed off the English coast 26 April 1667, and off Harwich 8 June, now approached. A letter amongst the State Papers in the Record Office, dated 20 June 1667, tells us that the Dutch fleet was seen off Harwich on the 6 June, but the only result was that a few fishermen were frightened, and that some of the Dutchmen landed and drove off some cattle. On the 10th the navy came within shot of Sheerness, and after some hours took the guns. On the 11th, by degrees, twenty or twenty-two Dutch ships were brought up to the narrow part of the river Medway, where ships had been sunk. Two and a half hours fighting on the following day made the Dutch masters of the chain. One guard ship after another was fired and blown up. The chain was broken by Captain Brackel by order of Van Ghent. Fire-ships were sent to destroy the English ships. The first hung on the chain, but the weight of the second snapped it. The Dutch ships went forward carrying destruction with them. The batteries on the banks of the river and the guns from. Upnor Castle were now brought into action, with the result that the enemy soon retired, leaving two ships stranded.