A HISTORY OF HERTFORDSHIRE 



rain-gauge have been presented, with the object of securing the per- 

 manence of the station. 



Bennlngton (Bennington House). Latitude : 51 53' 45" N. Longi- 

 tude : o 5' 20" W. Altitude : 407 feet. Observer : Rev. J. D. 

 Parker, LL.D., F.R.Met.Soc. Rain-gauge 5 inches in diameter, rim 

 i foot above the ground. The instruments are a considerable dis- 

 tance from the house and in a very exposed situation on the high 

 ground overlooking a great extent of undulating country on the north 

 and east. The situation is a very fine one and admirably adapted for 

 showing what is the climate of the Chalk hills of the north of the 

 county. There are numerous meteorological instruments. 



New Barnet (Gas Works). Latitude : 51 38' 5" N. Longitude : 

 o 10' 15" W. Altitude: 212 feet. Observer: T. H. Martin, 

 M.Inst.C.E. Rain-gauge 8 inches in diameter, rim i foot above 

 the ground. The instruments are near the office of the Barnet Gas 

 Company, apparently in a rather damp situation. Although not an 

 ideal one for the purpose, it well represents the London Clay district 

 on the north of London. This is the only Hertfordshire meteorological 

 station which is not on the Chalk. 



There is not one of the home counties which is better supplied, 

 for its area, with meteorological stations than is Hertfordshire, not- 

 withstanding the discontinuance of the Royston station, and the obser- 

 vatories are wide apart, and represent hill and valley, and chalky, 

 gravelly, and clayey soils. 



Tables I. to IV. give some of the results of observations taken at 

 these five stations during the twelve years 188710 1898. The annual 

 means, with extremes of temperature, are given in Table I. The 

 mean temperature of 48*3 is very little departed from at any station, 

 Royston only showing a greater departure than 0*3. It is remarkable 

 that this, the most northern station, should have a mean temperature 

 o'7 higher than that of any of the other four places. There is a very 

 close agreement between the mean minimum (or night) temperature at 

 each station except New Barnet where it is i'9 below the mean of the 

 other four : this is probably due in part to the kind of screen used, but 

 chiefly to the low position and the nature of the subsoil, London Clay, 

 which retains moisture and induces ground-fogs by which the air is 

 rendered colder at night than it would be in a higher position and on 

 a drier stratum. The clay is however here capped by a thin stratum 

 of gravel. The mean maximum (or day) temperatures are in still closer 

 agreement, the excess at Royston and New Barnet being fully accounted 

 for by the ' Glaisher ' stand being used at these two places. This, as 

 already mentioned, accounts for the greater range of temperature at 

 Royston and New Barnet than at Berkhamsted, St. Albans, and Ben- 

 nington. The only other point in this table calling for remark is the 

 small number of rainy days registered at New Barnet owing to the omis- 

 sion of the measurement of small falls of rain and snow, but this does not 

 affect the amount registered. 



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