The smallness of the difference between the annual mean temperature of Orkney and that of Kew is really due to the mildness of our winters. Taking the mean of the three winter months, we find that of Orkney to be almost the same as that of Kew, and slightly higher than that of Alnwick. For the three summer months, however, Orkney is three degrees colder than Alnwick and eight degrees colder than Kew. The hottest day in Orkney during the last thirty years only reached 76°, while at Kew 92° was recorded. The extent to which the sea influences our climate can best be seen by comparing it with that of an inland or continental station of similar latitude. Winnipeg, in the province of Manitoba, formerly well known to Orkney men as Fort Garry in the Red River Settlement, lies in nearly the same latitude as London. Its mean temperature, however, during the three winter months is only 0·9°, or thirty-one degrees below freezing-point, and thirty-eight degrees lower than that of Orkney; in summer it is 66°, or thirteen degrees above that of Orkney. Not only is our climate ruled by the sea; it is ruled by a sea whose waters are themselves somewhat warmer than their latitude might lead us to expect. The temperature of the ocean is often affected by currents, bringing water either from warmer or from colder regions. In the case of the ocean waters round our coasts, the movement is from the south-west. This movement is due at first to the Gulf Stream, which carries a great mass of warm water from the Gulf of Mexico into the North Atlantic, and afterwards to a surface drift caused by the prevailing south-westerly winds. Our coast waters are therefore somewhat warmer than they would be if there were no such movement, and much warmer than if there were a current in the opposite direction, sweeping along the shores of Norway from the northern ocean. If we compare our climate with that of Nain, in Labrador, which lies in nearly the same latitude, and is also on the Atlantic coast, we shall see how much depends upon the ocean currents. The cold Arctic current which washes the Labrador coast, bringing with it melting icebergs, snow, and fog, reduces the mean annual temperature of Nain to less than 26°, more than nineteen degrees below that of Orkney. While the climate of oceanic islands is benefited by the equable temperature of the ocean, it is often marked by excessive moisture and rainfall. Yet even in this matter we shall see that Orkney has little to complain of, while, of course, serious droughts are practically unknown.