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XXXVIII. On the Meteorology of England in the year 1847. 

 J[y James Glatsher,^^^'., of the Royal Observatory, Green- 

 wich *. 



THE meteorological returns for the year 1847 furnished to 

 the Registrar- General were from about thirty different 

 stations, situated between the latitudes of 51^° and 55° ^ and 

 between the longitudes of 5\° W. and 1:^° E. of Greenwich. 

 The elevations of the different places varied from 30 feet to 

 350 feet above the level of the sea. 



The monthly returns in each quarter were published in 

 their respective quarterly reports, but only the monthly values 

 corresponding to the limes of the observations, and not 

 those showing the mean values for the month ; these were 

 reduced to mean values for the formation of the quarterly 

 tables; but the corrections used in their reduction were those 

 deduced from three years' observations only ; since that time 

 I have formed tables from the five years' Greenwich observa- 

 tions ending December 31, 1845f, and have reduced the ob- 

 servations again by these values. The true monthly values 

 thus found will probably appear in a future Annual Report of 

 the Registrar-General. 



On discussing the true monthly values, it was found that 

 the temperature of the air decreased from the month of January 

 to that of February at all places south of the latitude 52°; 

 that at places situated near this parallel the temperatures of 

 these two months were nearly the same, and that north of this 

 parallel there was an increase of temperature from January 

 to February. Therefore the coldest month in the year, at 

 places whose latitude was less than 52°, was February, and at 

 places north of this parallel was January. The hottest month 

 at all places was July. By taking the monthly means from 

 the mean annual temperature, the annual variation is shown. 

 It was found to be a single progression, having one ascending 

 branch and one descending branch, being nearly identical 

 with that shown in the tension of vapour. This evidence is 

 conclusive upon the dependence of the monthly march of the 

 vapour upon the temperature ; each element has one ascending 

 branch and one descending branch, and the march is harmo- 

 nious. 



The only other circumstance with respect to temperature 

 to which I need allude, is the fact, that whilst the decrease 

 of temperature month by month proceeded regularly in the 



* Communicated by the Author. 



t See Philosophical Transactions, part i. 1 848, 



