EE 
’ 
eo 
Influence of the Atmosphere on the Electro-Galvanic Column. 47 
Nimbus, or Ratnctoup, may be subdivided, and described 
shortly, as stormcloud, thundercloud, &e. 
Hatos will be called Moonrrnes, Sunrines, &c. 
Coronas will be called Mooncrowns, &c. But I give this 
merely as an imperfect specimen of the nomenelature I am 
making, and which I shall publish and give in your Magazine in 
a short time: meanwhile I shall adopt these words of Saxon de- 
rivation in my journal, and give an explanation in the notes to 
those not inserted here. 
I am, &c. 
Tuomas Forsrer. 
XI. On the Influence of the Atmosphere on the Electro- Galvanic 
Column of M.De Luc. By Mr. J.Tarum. 
To Mr. Tilloch. 
Sir, — ben vecertibees various accounts of Mr. De Luc’s electrical 
column have appeared in your Magazine, I do not recollect that 
any journal of its action as connected with atmospherical in- 
fluence has yet appeared. Having long observed the very con- 
siderable alteration which every thermometrical change in the 
atmosphere produced on the operation of this instrument, I 
determined on keeping a regular journal, and noticing its cor- 
responding change with those indicated by the barometer, ther- 
mometer, De Luc’s hygrometer, and the direction of the wind, 
The results of my observations as deduced from my daily register 
of those instruments have convinced me that the greatest changes 
in the oscillations of the ball on De Luc’s columns are chiefly, 
if not entirely owing to the increased temperature of the at- 
mosphere, and not to its moisture, as some of my philosophical 
friends had supposed. By the following extract of my journal, 
it appears that when the thermometer was 52° and hygrometer 
81°, the ball of the columns oscillated only 248 times in a mi- 
nute; but when the thermometer was 56° and the hygrometer 
50°, it oscillated 284 times ; a satisfactory proof that the heat 
and not the moisture of the atmosphere increased the action of the 
instrument. In the latter case, | had removed the instrument 
to the gallery of my lecture-room, where the thermometer was 
14° higher, ard the hygrometer 5° drier than at the place from 
whence it was removed. 
It is proper also to add, that from the Ist till the 13th of the 
month the thermometer and hygrometer were not in the same 
apartment with the electrical columns, a circumstance which 
may haye occasioned some difference in the results, Since that 
period 
