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XIII. Farther Experiments relating to the Decompojition of 
dephlogijlicated and inflammable Air . By Jofeph Prieftley, 
LL.D. F. R. S. 
Read April 7, 1 79 1 • 
T HE do&rine of phlogifton, and that of the decompojition 
of water , have long engaged the attention of philo- 
fophical chemifts, and experiments have fometimes feemed to 
favour one conclufion, and fometimes an oppofite one. I have 
myfelf been very differently inclined at different times, as ap- 
pears in my publications on the fubjeft ; and I am hardly fen- 
fible of a wifli which way this important controverfy, as it 
may be called, be decided, notwithftanding the part that I have 
taken in it. I cannot help thinking, however, that the expe- 
riments, an account of which I (hall now lay before the So- 
ciety, are decifive in favour of the compoiition of an acid from 
dephlogifticated and inflammable air ; and, therefore, that the 
opinion of thefe two kinds of air neceffarily compofing water 
cannot be well founded. It is, indeed, fufficiently evident, 
that the fame elements likewife compofe fixed air , and there- 
fore it is the lefs extraordinary that they fhould compofe ano- 
ther acid. 
The do&rine of phlogifton I would, however, obferve, will 
not be affected by the mo ft decifive proof of the compoiition 
of water from dephlogifticated and inflammable air ; fince this 
would 
