THE SOCIETY'S GARDEN AT CHISWICK. 109 



perature between these extremes was 99.j degrees. This exceeded 

 the range at 1 foot deep by 63'degrees. The maximum tempe- 

 rature of the air exceeded the maximum at 1 foot deep by 30J° ; 

 and the minimum temperature of the air fell 37" below the 

 minimum at 1 foot deep. Hence the temperature of the air fell 

 more beneath the lower limit of the range of ground temperature 

 tlian it rose above the higher limit of the same. 



The hottest year as regards the temperature of the earth, 1846, 

 afforded a mean temperature of 52° 32' at 1 foot deep ; and 

 52° 85' at 2 feet deep. In the coldest year, 1845, tlie mean 

 temperature at 1 foot deep was 48° 95'; and at 2 feet deep 

 49° 44'. The respective differences of tlie two thermometers in 

 these hottest and coldest years were 3° 37' at 1 foot deep, and 

 3^ 41' at 2 feet. The mean temperature of the air was 51° 45' 

 in 1846, and 47° 92' in 1845 ; the difference being 3' 53'. 



On the average of the six years the earth is coldest in Feb- 

 ruary, and warmest in July. The mean temperature of the air 

 is also highest in July, but it is lowest in January. Throughout 

 the months the gradations of temperature are not uniform. The 

 monthly progression is as follows : — 



Temperature increases. 

 Feb. Mar. April. May. June. July. 



Temperature decreases. 



Aug. Sept. Oct. Nov. Dec. Jan. Feb. 



1 foot deep .1-12 4-02 5-97 5-59 6-04 1-62 1-07 



2 feet deep . 0-42 2-91 5-30 5-65 5-20 1-95 1-45 

 Air 2-24 4-84 5-93 6-48 7-29 0-10 — 



XVII. — Oti the most economical mode of forcing SeaTtale. By 

 Robert Errington, Gardener to Sir Philip de Malpas Grey 

 Egerton, Bart., M.P., F.H.S. 



(Communicated Jan. 29, 1848.) 

 One of the best features of modern horticulture is the simplicity, 

 and of course economy, with which many of our finer garden 

 productions can now be obtained. This may not be sufficiently 

 obvious at first sights but a just comparison of the products of a 

 highly cultivated modern garden of any pretensions, with one of 

 some twenty or thirty years ago, will bear ample testimony to 



