Gerald of Wales on the topography of Ireland
Chapter IV: Of the surface of Ireland, and its inequalities; and of the fertility of the soil.
Ireland is a country of uneven surface, and mountainous; the soil is friable and moist, well wooded, and marshy; it is truly a desert land, without roads, but well watered. Here you may see standing waters on the tops of the mountains, for pools and lakes are found on the summits of lofty and steep hills. There are, however, in some places very beautiful plains, though of limited extent in comparison with the woods. On almost all sides, and towards the sea-coast, the land is very low, but in the interior it rises into hills of various elevations and mountains of vast height; not only the surrounding country, but also the central districts, being rather sandy than rocky. The tillage land is exuberantly rich, the fields yielding large crops of corn; and herds of cattle are fed on the mountains. The woods abound with wild animals; but this island is more productive in pasture than in corn, in grass than in grain. The crops give great promise when in the blade, still more in the straw, but less in the ear; for the grains of wheat are shrivelled and small, and can hardly be separated from the chaff by dint of winnowing. The fields are luxuriantly covered, and the barns loaded with the produce. The granaries only show scanty returns.
Chapter V: On the prevalence of winds and rain; and their causes.
The crops which the spring brings forth, and the summer nourishes and advances, are harvested with difficulty, on account of the autumnal rains. For this country is exposed more than others to storms of wind and deluges of rain. A wind blowing transversely from the north west, and more frequent and violent than any other winds, prevails here; the blast either bending or uprooting all the trees standing on high ground in the western districts, which are exposed to its sweep. This arises from the land, surrounded on all sides by a vast sea and open to the winds, not having in those parts any solid shelter and protection, either distant or near. Add to this, that the waters attracted in clouds, and collected together by the high temperature of that region, and yet neither exhaled by fiery atmospheric heat, nor congealed by the coldness of the air and converted into snow or hail, at last burst in copious showers of rain. In short, this country, like other mountainous regions, generates and nourishes most abundant rains. For the heat evaporating from the high lands by excessive wet, the moisture which they attract is easily converted into its native element. And it is usually distinguished by various names, according to its various elevations. While yet hanging about the hills, it is called mist; when it rises higher, and, floating in the atmosphere, is quite disengaged from the earth, it becomes clouds; again descending in drops or particles, it is called snow or rain, according as it is solid or liquid. Thus, Ireland, Wales, and Scotland are subject to much rain.