1867.] Br. Everett on Atmospheric Electricity. 



195 



months. Stored up, yet held in feeble combination, a combination so weak 

 that the vital forces of the fresh-growing vegetation can easily overcome it, 

 and resolve once more into carbonate of lime, carbon, and oxygen the bi- 

 carbonate of lime contained in the water *. 



Thus beautifully are the necessary irregularities in the purifying action 

 of the plant compensated and provided for, that the balance of existence 

 between the animal and vegetable organisms be not disturbed or overthrown, 

 and thus additional proof is furnished, if such were needed, of the wisdom 

 of that creative power that has ordered all things to work together for good, 

 and by endowing certain bodies with such seemingly minute and insignifi- 

 cant affinities, maintains the glorious harmony of the whole. 



II. " Results of Observations of Atmospheric Electricity at Kew 

 Observatory^ and at Windsor^ Nova Scotia.^' By Joseph D. 

 EvERETTj D.C.L., F.R.S.E., Assistant to the Professor of Ma- 

 thematics iu the University of Glasgow. Communicated by Sir 

 William Thomson. Received October 14^ 1887. 



(Abstract.) 



The paper commences with an account of the concluding observations 

 taken by the author at Windsor, N.S., of which the previous portion has 

 already been published in the ' Proceedings,' vols. xii. & xiv. 



It then goes on to describe the self-recording apparatus employed at 

 Kew Observatory for the observation of atmospheric electricity, and the 

 method of procedure employed in measuring and reducing the curves thus 

 obtained, this portion of the work having been performed in the Physical 

 Laboratory of the University of Glasgow. 



Tables are given showing the mean hourly values of the electrical potential 

 for each month, and the mean monthly values are hence derived. These 

 values for Kew are compared with the corresponding values for Windsor, 

 N.S., and remarkable differences are shown to exist between the curves, 

 both diurnal and annual, for the two places. 



The hourly means at Kew for the mean of the year are represented by 

 the following numbers : — 



23^ 



0^ 



l'^ 



2'' 



3'^ 



4^ 



5^^ 



6'^ 





1-91 



1-96 



1-92 



1-93 



1-95 



2-08 



2-29 



2-58 



2-86 





9'^ 



10^^ 



11'^ 



12^^ 



13'^ 





15^^ 



16'^ 



2-96 



2-93 



2-74 



2'42 



2-12 



1-86 



1-68 



1-58 



1-54 



17'^ 



18^^ 



19^^ 



20^^ 



21'^ 



22^^ 









1-52 



1-64 



1-96 



2-26 



2-28 



2-13. 









These numbers indicate a principal maximum between S^' and 9'', and a 



The rapid growth of submerged vegetation in rivers and waters containing a con- 

 siderable amount of carbonate of lime must have been observed by all interested in the 

 subject, iu some cases obliging the cleansing of such streams three or four times during 

 the year. 



