some areas over 100 inches a year—and the relatively dry east coast tracts where the average may be less than 20 inches a year. Although the English farmer may complain of droughts, a period of as long as three weeks without rain is exceptional, and droughts disastrous to agriculture, so well known in other lands, do not occur in Britain. Indeed the drier years are usually marked by high crop yields.
Although Britain's fogs, to a large extent accentuated by the smoky atmosphere of London and other big cities, have attained world-wide notoriety, severe fogs are nowadays rarer than formerly, and are seldom widespread, though occasionally, as in the winter of 1952-53, fog persists for many consecutive days in certain areas. The hours of sunshine throughout the year are relatively low owing to broken cloud cover; the average is between 24 and 38 per cent of the possible total.
With its mild climate and varied soils, Britain has a complicated pattern of natural vegetation cover. When the islands were first settled, oak woodland doubtless covered the greater part of the lowland, giving place to thin forests of Scots fir on higher or sandy ground, interrupted by extensive marshlands and perhaps some open moorland. In the course of the centuries nearly all the forests have been cleared so that forest and woodland now occupy only about 6 per cent of the surface of the country. Midland Britain seems superficially to be well wooded because of the numerous hedgerows and isolated trees.
The hilly moorland with its famous heather (and cotton grass in the wetter parts), with its numerous hill grasses and the bracken fern, is a semi-natural wild vegetation. Most of Lowland Britain consists either of grass pastureland representing centuries of careful management, or ploughland. Because of the well-distributed rainfall coming in almost equal amounts in each month of the year, streams rarely dry up and grass remains green throughout the year.
The people who now inhabit the British Isles are descended mainly from the people who inhabited them nearly nine centuries ago. The last of a long succession of invaders and colonizers from Scandinavia and the continent of Europe were the Normans, a branch of the Norsemen or Scandinavian Vikings who, after settling in northern France, intermarrying with the French, and assimilating the French language and customs, crossed to England and conquered it in 1066.
It is neither possible nor suitable to attempt in this chapter to estimate the relative importance of various early peoples—pre-Celtic, Celtic, Roman, Anglo-Saxon and Norse—in the ancestry of the present English, Scots, Welsh and Irish. It is significant, however, that over most of England and the Lowlands of Scotland the language which soon came to predominate was English, mainly a marriage of Anglo-Saxon and Norman-French, while the use of Celtic languages persisted in Wales, Cornwall, the Isle of Man, the Highlands of Scotland and Ireland.
The available records do not permit of any precise estimates of the size of population or of the extent or direction of population movement until the beginning of the nineteenth century. It is believed that at the end of the eleventh century the population of Great Britain was of the order of two million, while at the end of the seventeenth a reasonable contemporary estimate put the population of England and Wales at 5½ million and the population of Scotland at about one million. Natural increase was the main factor in this slow growth, though it was kept down in Britain, as in all countries before the development of medical science, by high death rates and particularly by very high infant and maternal mortality. Immigration from the continent of Europe, e.g., of Flemish weavers, played some part at certain times.
From the beginning of the nineteenth century, information about the British people, their number, sex, age, geographical distribution, births, deaths, marriages, occupations, language and family structure, is relatively plentiful and reliable. Most of it is derived from
