60 J. HOPKIjSTSON — METEOROLOGICAL OBSEEVATIONS 



The year 1893 was remarkably "warm, especially during the 

 spring. The mean daily range of temperature was large ; the 

 absolute range also was great, the rather low minimum of 14° -7 

 occurring in January, and the high maximum of 91°-0 in August. 

 The temperature was above the average in every one of the six 

 months of spring and summer (March to August) ; as much as 4^° 

 above it in the spring, and 2^° above it in the summer. The only 

 months with a temperature appreciably below the average were 

 January and November. The change from summer to autumn 

 was marked, September being 9° colder than August. The mean 

 pressure of the atmosphere was considerably above the average of 

 that of the ten years 1877-86 at Watford. The lowest pressure 

 recorded at 9 a.m. was 28-753 ins. on 21st February, and the 

 highest was 30'750 ins. on 30th December, giving a range of 

 1'997 in.* The rainfall was much below the average of that of the 

 ten years 1877-86, and considerably below a long-period average. 

 The number of wet days also was small. March, April, June, and 

 September were very dry months ; October was very wet. The 

 air was dry and the sky bright. The prevailing direction of the 

 wind was south-west and west. 



In the winter of 1892-93 (Dec. to Feb.) the mean pressure of the 

 atmosphere was rather low, the mean temperature was rather low, 

 with an average mean daily range, and the humidity, cloud, and 

 rainfall were about the average, but rain fell on an unusually large 

 number of days. There was a month of very cold weather (22nd 

 Dec. to 13th Jan.), and on the other hand there were fifteen days 

 in succession in Februaiy (8th to 22nd) without a single night on 

 which the temperature of the air fell below freezing-point. 



In the spring (March to May) the mean pressure of the 

 atmosphere was very high, the mean temperature was excessively 

 high, with a very great mean daily range, the air was very dry, 

 the sky very bright, and the rainfall excessively small, on an 

 unusually small number of days. This spring will for long be 

 memorable for its warmth, brightness, and diyness, being probably 

 the warmest, brightest, and driest since the year 1840, or for 

 more than half a century. While, however, the days were 

 abnormally warm, the nights were rather colder than usual. We 

 had only, at 9 a.m., two-thirds the average amount of cloud. The 

 rainfall was only about one -third the average for this part of 

 Hertfordshire for the last haK-centuiy, and the number of rainy 

 days was even smaller in proportion than the amount of rain. 



In the summer (June to August) the mean pressure of the 

 atmosphere was rather high, the mean temperature was a little 

 above the average, with a large mean daily range, the air was 

 very dry, the sky rather bright, and the rainfall very small, 

 but on an average number of days. The nights were considerably 

 colder than usual, the excess of temperature being entirely due 

 to the warmth of the days. 



* The pressure at 3 p.m. on 21st February was 28'689 ins., increasing the 

 range for the year to 2 "061 ins. 



