ATMOSPHERIC ELECTRICITY. 



On the Electricity of the Atmosphere in clear Weather. — Connexion between Electricity and Me- 

 teorology. — Apparatus for observing the Electricity of the Atmosphere. — Insulated elevated Rod. — 

 Portable Apparatus made of a fishing Rod. — Saussure's Electroscope and his Mode of estimating 

 the Value of the Divergences. — Occasional Use of the Galvanometer. — The 01 dinary Stale of the 

 Atmosphere. — Volta's Theory of the Origin of Atmospheric Electricity. — Inadequacy of the The- 

 ory of Chemical Origin. — The Author's Suggestion of the probable Influence of Friction. — Diur- 

 nal Variation of the Electricity. — Periodical hourly Variation. — Representation of the Rate of Va- 

 riation. — Maxima and Minima at a given Parallel. — Schiibler's Observations. — Annual Variation 

 of the Electncity. — Variation of the daily Maxima and Minima. — Arago's Repetition of Schiibler's 

 Observations. — Local Variations of the Electricity. — Influence of particular Localities.. Buildings, 

 &c. — No satisfactory Explanation yet given of the Variations. — Correspondence between Electric 

 and Magnetic Variations. — Becquerel's Explanation of the Phenomena of Variation. — Distribution 

 of Electricity of the Air. — Negative State of the Earth. — Character of the lower Stratum of Air. — 

 Increase of Electric Charge in the higher Strata of Air. — Decrease in the lower Strata. — Compar- 

 ative Electric Character of different Strata. — Formulae for the comparative Electricity of two 

 Strata. — Electricity of the Air in clouded Weather. — Preliminary. — Schiibler's Observations. — Ta- 

 ble of Observations explained. 



