LYING as it does midway between India and Australia, Java forms a climatological link between the two great British Dominions, and we recognise the appropriateness of the compliment implied in the choice of English as the second language in which this important outcome of Dutch enterprise is published. Tables are given of the mean monthly rainfall, number of rain days, and mean daily maximum rainfall (for each month) at 1061 stations in Java from observations taken between 1879 and 1911. Dr. van Bemmelen discusses the trustworthiness of the data, which are far from uniform. Obviously fallacious records have been eliminated, and there is reason to believe that the data here given compare well with those available for other tropical countries. Observations were made to the nearest millimetre, so that the critical rainfall which determines whether or not a day is to be counted as a rain day is 0.5 mm., or 0.02 in., i.e. four times the amount taken as determining a rain day in this country. As an example of the variability of monthly rainfall in Java, the case is cited of one station where in September, 1902, the rainfall was 12 mm., and in September, 1904, 896 mm. The greatest average annual rainfall recorded at any station in Java is 8305 mm., and the least 882 mm., but for both stations quoted the average was only for the short period of seven years, and experience shows that runs of seven years may occur with every year above or every year below the long-period average. The wettest year ever recorded at any station was 10,112 mm. at Sirah Kentjong, Kediri, in 1909, and the greatest fall in twenty-four hours was 511 mm. at Besokor, Semarang, on January 31, 1901. Perhaps I may be pardoned if I remind those who keep metric and vulgar statistics in separate compartments of their brains that these figures are equivalent to 398.1 and 20.1 in. respectively.