Powell sank a pit at Cwmbach, and during the next few years he opened another four pits. In the next few years, other local entrepreneurs now became involved in the expansion of the coal trade, including David Williams at Ynysgynon and David Davis at Blaengwawr, as well as the latter's son David Davis, Maesyffynnon. They were joined by newcomers such as Crawshay Bailey at Aberaman and, in due course, George Elliot in the lower part of the valley. This coal was valuable for steam railways and steam ships, and an export trade began, via the Taff Vale Railway and the port of Cardiff. The population of the parish rose from 6,471 in 1841 to 14,999 in 1851 and 32,299 in 1861 and John Davies described it as "the most dynamic place in Wales". In 1851, the Admiralty decided to use Welsh steam coal in ships of the Royal Navy, and this decision boosted the reputation of Aberdare's product and launched a huge international export market. Coal mined in Aberdare parish rose from in 1844 to in 1850, and the coal trade, which after 1875 was the chief support of the town, soon reached huge dimensions. The growth of the coal trade inevitably led to a number of industrial disputes, some of which were local and others which affected the wider coalfield. Trade unionism began to appear in the Aberdare Valley at intervals from the 1830s onwards but the first significant manifestation occurred during the Aberdare Strike of 1857–8. The dispute was initiated by the depression in trade which followed the Crimean War and saw the local coal owners successfully impose a reduction in wages. The dispute did, however, witness an early manifestation of mass trade unionism amongst the miners of the valley and although unsuccessful the dispute saw the emergence of a stronger sense of solidarity amongst the miners. Steam coal was subsequently found in the Rhondda and further west, but many of the great companies of the Welsh coal industry's Gilded Age started operation in Aberdare and the lower Cynon Valley, including those of Samuel Thomas, David Davies and Sons, Nixon's Navigation and Powell Duffryn. During the early years of the twentieth century, the Aberdare valley became the focus of increased militancy among the mining workforce and an unofficial strike by 11,000 miners in the district from 20 October 1910 unyil 2 February 1911 attracted much attention at the