THE ENGLISH LAKE DISTRICT. 119 



at Seathwaite, in December, was 19°, and in January 18°. On December 16th, 

 the thermometer at Manchester and Linslade fell to 6°, and, at Wakefield, to 9°*5 ; 

 on January 3d, it fell at London to 10° ; and, in the Midland Counties, Mr Lowe 

 estimated the extreme of cold at 4° below zero. 



The greatest depth of snow on the ground at one time in the vales of Wastdale 

 and Borrowdale was about 3 inches. The simultaneous fall at Liverpool and 

 London was 12 inches. On January 3d, the drifts over England and Wales, 

 according to Mr Glaisher, varied from 3 feet to 10, 12, and 15 feet ; they were 

 very deep at Derby and at Grantham, and upon the Norfolk coast. 



Hygrometrical Observations at the Mountain Stations. — The hygrome- 

 trical observations are so consistent with each other, and the resulting humidity 

 of the atmosphere at the different elevations is so accordant with theoretical 

 reasoning, that they carry with them a conviction of the faithfulness and of the 

 care with which they must have been taken and recorded. I have not attempted 

 to correct the dry and wet bulb observations at Wastdale, for the variation in 

 temperature corresponding to the different hours in the day at which the moun- 

 tain readings were taken, as the law of the horary fluctuation in the temper- 

 atures of the air and of evaporation for this latitude is unknown. 



The very valuable tables compiled by Mr Glaisher for the latitude of Green- 

 wich, it is believed would not apply to this district, and any forced or modified 

 application of them to a mountain valley would be almost certain to vitiate the 

 results. The chief points aimed at were, to ascertain the complement of the dew 

 point and the relative degree of humidity at various heights above the sea and 

 valley, and these, by far the most important deductions, will be but slightly if at 

 all affected, by the interim variation of the air and evaporation temperatures in the 

 valley. The observations are therefore tabulated as they were taken on the spot, 

 simply corrected for slight instrumental errors. 



In computing the decrease of temperature upwards in the atmosphere, the 

 temperature assumed for the valley is the mean of the two observations taken on 

 leaving and returning to the hamlet of Wastdale Head. 



The hygrometrical results for the years 1852 and 1853 are in essential accord- 

 ance with each other, and show that whilst the absolute quantity of vapour in the 

 atmosphere gradually diminishes, the degree of humidity {or the dampness of the air 

 relative to its temperature) proportionately increases, in ascending above the compa- 

 ratively level surface of the earth. 



The only exception to the law occurs on Lingmell, where the humidity indi- 

 cated in both years is slightly greater than at Sprinkling Tarn, about 120 feet above 

 it — the additional quantity of vapour requisite to produce complete saturation 

 being the same at both places. The stations are situated at opposite extremities 

 of the valley, and the difference is no doubt attributable to local causes. In 1852. 



