The variations of temperature and rainfall in the British Isles during a period of two centuries or so have been studied on several occasions, but hitherto the subject of wind direction, equally im-Portant from the* meteorological standpoint, has been neglected. This compilation attempts t o remedy the omission. X fair amount of material is available, but the quality is very variable. Systematic weather diaries commence towards the end of the seventeenth century, giving one or more observations daily; at first there are serious gaps, but later the records become continuous. I t w a s found that the wind observations in many of the earlier weather diaries had never been tabulated ; the collection of the material has therefore been a decidedly laborious task. The presentation of the results also required thought. To give the actual frequencies of winds from eight points for all the years available would take a great deal of space; moreover, in that form the variations from year t o year are not readily grasped. Hence the various directions have been combined into " direction-frequency vectors, " which arc computed by assigning unit value to each observation of wind direction, irrespective of force. Although this practice does not give the actual resultant air-flow, for the earlier years it is the only practical method, and moreover it actually has certain advan. tages. The climatic character of all winds except the lightest depends more on their direction than on their force; for example, an east wind of 10 miles per hour differs more in its climatic character from a west wind of 10 miles per hour than the latter does from a west wind of 30 miles per hour, although the vector differences between them are the same. Secondly, the nuinerica! value of the vector, which we have termed the " constancy," gives a better idea of the steadiness of the wind from one direction than it would if account were taken o f velocity. The resultant directior.is literally the mean direction; this and the '' constancy " are analogous to mean temperature and the inverse of standard deviation, while direction frequencies are analogous to temperature frequencies. I t may be remarked that a similar method of computing resultant direction and " constancy " from daily observations of wind direction only has been in use for many years in t h e 8' Reseau Mondial."From the available material a choice was made of the three representative stations London, Edinburgh and Dublin, but one g a p in the London record was partly filled by series of observations from the " Downs " and one in the Edinburgh record by a series from Perth. Wherever possible, every change of series is covered by a n overlap, but no actual reduction from one series to another has been attempted in the main tables. T h e results are given for

T h e mean annual rainfall in each five-degree zone was calculated separately for the land and sea areas by a planimetric method, using the best available rainfall charts for each country or ocean. The results show maxima over the land in latitude o -~O S . , and 5oo-6o0S., a minimum in latitude 30's. ; over the sea, maxima in 50°N., -1o'N. and 40~-45~S., minima in 40°-500N.,