1. _Temperature._--The mean temperature of Hertfordshire, as deduced from the above observations, is 48.3 deg.. It has varied from 47.0 deg. in 1887 to 50.2 deg. in 1898. The mean daily range is 15.9 deg.. It was the least (14.2 deg.) in 1888, and the greatest (18.1 deg.) in 1893. The mean temperature of the seasons is as follows: spring 46.6 deg., summer 60.2 deg., autumn 49.2 deg., winter 37.2 deg.. The warmest month is July, with a mean temperature of 61.0 deg.; the coldest is January, with a mean of 36.1 deg.. August is very little colder than July. In these two months only has the temperature never been below freezing-point (32 deg.). In December and January only has it never exceeded 62 deg.. It increases most rapidly during the month of May, and decreases most rapidly during September and October. 2. _Humidity._--The relative humidity of the air, that is the amount of moisture it contains short of complete saturation which is represented by 100, is, at 9 A.M., 82. It has varied from 78 in 1893 to 85 in 1888 and 1889. The air is much drier in spring and summer (78 and 75) than it is in autumn and winter (86 and 89). There is the least amount of moisture in the air from April to August (74 to 78), and the greatest from November to January (90). 3. _Cloud._--The mean amount of cloud at 9 A.M., from 0 (clear sky) to 10 (completely overcast), is 6.7. It has varied from 6.0 in 1893 to 7.4 in 1888. Spring, summer, and autumn are about equally cloudy (6.5 to 6.6), and winter is considerably more so (7.2). The sky at 9 A.M. is brightest in September (6.0) and most cloudy in November and January (7.5). 4. _Sunshine._--At Berkhampstead only have records of bright sunshine been taken for the whole of the twelve years. Throughout the year the sun shines brightly there for nearly four hours a day (3.9). The average duration in spring is 5.0, in summer 5.8, in autumn 3.2, and in winter 1.6. The duration is least in December and greatest in May; the sun shining for rather more than an hour a day in December and nearly six hours and a half in May. An apparent discrepancy between this and the preceding section is due to a bright day often following a cloudy morning and _vice versa_. 5. _Wind._--The prevailing direction of the wind, as recorded at Berkhampstead, St. Albans and Bennington, is from S.W. (sixty-one days in the year) to W. (sixty-two days), and the next most frequent winds are N. to N.E. and S. (each about thirty-seven days). The least frequent are S.E. (twenty-five days). About forty-four days in the year are recorded as calm.