§ 12. The same laws and the same limitations which are operative in determining the character and degree of specialisation of countries or large areas are also seen to apply to smaller districts, towns, and streets. Industries engaged in producing valuable, durable material objects in wide demand are locally specialised; those engaged in providing bulky perishable non-material goods, or goods in narrow demand, are unspecialised. England, where internal intercourse has been most highly developed, and where internal competition has been freest and keenest, shows the most advanced specialisation in several of its staple industries. The concentration of cotton spinning in South Lancashire is an example, the full significance of which often escapes notice. From the beginning South Lancashire was the chief seat of the industry, but it is now far more concentrated than was the case a century ago. Several of the most valuable inventions in spinning were first applied in Derbyshire, in Nottingham, at Birmingham, and in Scotland. Scotland then competed closely in weaving with Lancashire. Now the Scotch industry is confined to certain specialities. In spite of the enormous growth of the manufacture, the local area it covers is even narrower than last century. Within Lancashire itself the actual area of production has shrunk to some 25 square miles in the extreme south, while the two great cities are further specialised--Liverpool as the market for cotton, Manchester for yarn and cotton cloths.