154 IV. CLIMATE. 



Luke Howard long ago showed tliat the recorded tempe- 

 ratures were too high ; more truly indicating the artificial 

 warmth of a large town, than the real climate of its 

 latitude or geographical position. Succeeding observers 

 have con'oborated this view ; but still various writers 

 have gone on parrot-wise repeating and citing the regis- 

 ters of the Royal Society, to the neglect of much better 

 records. Consequently, the mean temperature of London 

 is commonly given as 50 of Fahrenheit and upwards, in 

 tables of temperature compiled by foreign authors, 

 equally as by those of England. In his ' Climate of 

 London ' Howard made the mean temperature of the 

 ■vicinity of the Metropolis, at the distance of a few miles, 

 only 48i^ of Fahrenheit; a temperature which appears 

 somewhat below truth. Other observers have stated 49, 

 usually with a fraction or decimal over, as the result of 

 their registers in the neighbourhood of London. It 

 would hence seem that no wide error can be committed 

 in assuming 50 Fahrenheit, as the mean temperature at 

 the level of the sea, in latitude 51, that is, half a degree 

 southward of London. 



Towai'ds the extreme south-west of England (Penzance, 

 Helston, Plj^mouth) thermometrical registers give so high 

 a mean as 53 ; which would be a rise of two degrees in 

 temperature for a single degree of latitude. This may 

 be considered a local and exceptional case ; the high 

 mean temperature decreasing rapidly eastwai'd as well as 

 northward. On the coasts of Dorset and Hants, the 

 mean appears to be about 51 of Fahrenheit. It has been 

 asserted that Malvern, situate near the conterminous 

 borders of "Worcester and Hereford shires, far inland and 

 some height above the sea-level, has an annual mean 

 rather exceeding 49|-. And a higher mean has been 

 given for Cheltenham, in the inland part of Glou- 



