This observation naturally leads up to a consideration of the effect of the proximity of the sea upon climate. Water heats more slowly than land, but also cools more slowly, and therefore the proximity of large masses of water has, speaking generally, a moderating influence upon climate, producing the so-called maritime climate. In the case of the British Isles this effect is very marked, because the ocean to the west of us is unusually warm, and the circulation of the atmosphere is such that the prevailing winds of winter blow towards us from the warmer parts of this ocean, while the fact that the summer winds often have a northerly component helps to keep the summer temperatures down. The peculiar conditions of the British Islands illustrate the fact that climate does not depend upon latitude alone, but may be greatly modified by local conditions, especially by the distribution of land and water, and the direction of the wind. Let us now sum up what has been said in regard to the main types of climate found in Europe. Round the Mediterranean basin we have an area with mild winters and warm summers, where the rain tends to fall during the winter season, making summer a period of drought. This climate extends beyond the limits of Europe into Northern Africa and Western Asia, and is separated from the regions of tropical climate, which have no winter and have rains at the hottest season, by a belt of desert. The western seaboard of Europe has a maritime climate, the sea tempering the winter, but diminishing the summer heat. The prevailing winds are westerly, and the rainfall is typically abundant and distributed throughout the year. On passing inwards this type of climate changes into the continental type, with cold winters and hot summers, and diminishing rainfall. Though precipitation occurs at all seasons of the year, it tends to be greatest in summer, giving, _e. g._ in parts of the Balkan States, a type eminently suited to the cereal maize, which needs more summer rain than wheat. If we bear in mind that North America is a large continent, and Europe a very small one, and that while Europe has no eastern seaboard, it is the eastern seaboard of America which faces Europe, we may realise that the climates of North America show a remarkable analogy to the European. On the western side we have in British Columbia and California respectively the same two types of maritime climate which occur in Europe, that is, British Columbia has a mild equable climate with abundant and equally distributed rainfall, and California has a Mediterranean climate.