In no part of Britain is the need for the "decentralization of industry" more urgent than in the South Wales coalfield. In the last five years research committees have considered schemes of large scale town-planning in anticipation of further development and also with a view to altering the present distribution of the population. These schemes include the creation of new urban centres in the coastal region to accommodate a large proportion of the population of the mining valleys. This would require a great extension of the means of communication, the development of cheap and rapid transport and the rise of manufacturing indus tries of a general character which would absorb an appreciable part of the coal output and provide variety in employment.
Prior to 1870 the leading place in the economic development of South Wales was held by the iron industry. Along the northern edge of the coalfield plentiful and readily accessible supplies of coal, iron ore and limestone occurred in close proximity. Consequently, in the first half of the 19th cen tury a narrow upland tract, extending for about 20 m. from Pontypool and Blaenavon to Hirwain, with its chief centre at Merthyr-Dowlais, became the greatest iron producing region in the world. The invention of processes for the large scale manu facture of steel and the resulting demand for richer and purer iron ores than those found in the coalfield, caused many of those works to be closed or to be transferred to the seaboard. Merthyr Tydfil, once the largest town in Wales, which in 1831 exceeded in population the aggregate of Newport, Cardiff and Swansea, is steadily declining owing to these changes ; in some of the old in land centres, such as Ebbw Vale, Rhymney and Dowlais, the manu facture of iron in specialized forms is still actively maintained. On the south-west of the coalfield the hill country extends to the coast line and in many places coal is mined within a short dis tance of tidal water. This is the anthracite region and since 1910 90% of British anthracite, the great bulk of which is exported, has been raised in South Wales.
The western ports, Llanelly, Swansea and Port Talbot, are not only centres of the coal export trade but their favourable situ ation has enabled them to develop great metallurgical industries the success of which depends upon supplies of cheap fuel. Of these the earliest and long the most important was the smelting of copper; Swansea became the centre of the world production of copper. Before the end of the 19th century, however, copper ores came to be generally smelted at the mines but refining processes are still carried on in the Swansea area which has also continued to increase the output of metallurgical products originating in the early copper industry. The refining of nickel, imported in a crude
state from Canada, is a new and flourishing industry.
In the last quarter of the 19th century the manufacture of tin plates and of galvanized iron became localized very largely in this region. This resulted from the establishment of steel works in the coastal section of the coal field, aided by the discovery that sheet steel was to be preferred to iron in the making of tin plates. Over 9o% of the export trade of British tin plates is concentrated in the port of Swansea, which in 1927 shipped 440,000 tons of tin plates and terne plates valued at £9,500,000. Owing to their high reputation, Welsh tin plates are imported into every country in the world, often in spite of high protective tariffs. More than 9o% of the zinc smelted in Britain is produced in the Swansea district (spelter works). The zinc is chiefly used in the making of alloys, brass, bronze, etc., but scarcely less important is the industry of manufacturing galva nized iron by coating iron plates with zinc. In 1927 721,000 tons of galvanized iron sheets were exported from Swansea.
The establishment of the oil refinery of the Anglo-Persian Oil Company at Skewen, near Swansea, has increased the trade of the port of Swansea by about 2,250,000 tons annually.
North Wales is more closely related in its economic life to Lancashire and the Midlands than to South Wales, for east to west routes are far more practicable than from north to south in Wales. The North Wales coalfield lies in the counties of Flint and Denbigh and extends for about 4o m. from south to north along the Dee valley. Although extensive, it is far less rich and varied in its output than the South Wales field. The annual output remains fairly constant at about 3,500,000 tons. The coal obtained is used chiefly for domestic purposes and for gas manufacture, the Cannel coal of Flintshire being specially reputed for its gas producing qualities. Thus, as the North Wales coal industry depends mainly upon the home market, it has suf fered relatively less in recent years than the South Wales coal field from the intense depression of the coal export trade. How ever, owing to excellent transport facilities by road, rail and canal, and the proximity of tidal water a great variety of indus tries has developed in this region and new ones are continually rising. In the inter-censal period 1911-1921 the proportional in crease of population was higher in Flintshire (14.8%) than in any county of England and Wales, being 1% higher than that of Mon mouthshire, which came second, and 2% higher than Glamorgan shire which was in the third place.