On the Re-action of Sulphuric Acid on Camphor. 425 
for along time unattended by rain, when the nights are 
clear, and small meteors, called falling stars, are numerous; 
when, |] say, these circnmstances happen together, I have 
observed that the bells of this column always ring with very 
irregular pulsations; and further, when rain succeeds such 
kind of weather, it commonly bappens that their pulsations 
become weak, or cease altogether, and the bells become st- 
dent: on the contrary, when the weather is fair, and when 
only diurnal cwmadi prevail, they usually pulsate regularly. 
An ingenious meteorologist suggested to me, the other day, 
that the irregular pulsation of the bells might be occasioned 
by the electric fluid’s passing downward to the earth in pud- 
sations, which might be the case when it was very irregu- 
larly distributed in the atmosphere. 
To me it appears that this irregular distribution of the 
electric fluid would be indicated by the multiform appear- 
ance of the cirrus cloud which I havedesenbed, for the par- 
ticular office of this cloud seems to be that of serving as a 
conductor of electricity. The same circumstance would 
also give rise to the occasional appearance of other modifi- 
cations. All however that can be said on this interesting 
subject at present is, éhat there seems to he a connection 
worth attending io between the kind of action of the column, 
and the kind of weather which prevails, indicated ly the 
various and peculiar appearances of the clouds, Future ob- 
servations may lead to the knowledge of adjunct circum- 
stances which may have their share in producing these 
changes. To engage the e»-operation of other meteorolo- 
gists, by which alone the science can be brought to any de- 
gree of periection, is the object T have in view in soliciting 
the favour that this may be inserted in your Philosophical 
Magazine. I remain, sir, 
Your constant reader and servant, 
St. Helen’s Place, June 14, 1811. THOMAS FORSTER. 
LXXI. Memoir on the different Compounds formed by the 
Re-action of Sulphuric Acid on Camphor. By M. Cue- 
VREUL*, 
Hayixe shown in my two former memoirs, that tanning 
substances, formed by the re-action of nitric acid upon many 
vegetable compounds, were combinations of that acid with 
different substances, the greater part of which are unknown 
* Aunales de Chimie, tome lxx. 
to 
