THE 
MONTHLY MAGAZINE. 


XXIX.] 
For MARCH, 1798. 

‘[Vot. V. 

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2 
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ORIGINAL COM 
To the Editor of the Monthly Magazine. 
SIR 
AVING undertaken to examine 
the principles of the new theory of 
chemiftry, I wifh to excite as much atten- 
tion as poflible to the fubject; and as 
your publication goes into the hands of 
all lovers of literature in England, I beg 
leave to make ufe of ‘it, in order to ftate, 
ina general way, what appear to me to 
be the ftrongeft objections to this fyftem, 
which has now reigned triumphant about 
twelve years, very few perions befides 
mylelf being advocates for the old doc- 
trine of phlogiftion. I have already 
publithed two pamphlets on the fubject, 
and I intend to continue the controverly 
till I have colleted all the evidence that 
thall be fufficient to decide the queftion ; 
and if in the iffue I fee reafon for fo do-, 
ing, I fhall publicly acknowledge my 
converfion to the doétrine that I now 
controvert, and fhall even take a pride in 
fo doing. In the mean time, having 
heard what has been advanced by fome 
very able advocates for the new fyftem, 
in anfwer to my firft pamphlet, I think I 
am pretty well apprized of all that ¢an 
be faid with refpeét to thofe experiments 
that are yet before us. But in time 
fomething more decifive may be produced. 
In reply to all that I have yet heard on 
the fubject, I would obferve, 
1. When ametal, viz. iron, is diffolv- 
ed in the vitriolic acid, the antiphlogittians 
fay, that the inflaminable air which is pro- 
eured does not come from the irox, but 
from the water, which is decompofed in 
the procefs. But, according to their 
theory, water confilts of two principles, 
hydrogen gas and oxygen, and therefore, if - 
the hydrogen be fet at liberty, in the form 
of inflammable air, there ought to re- 
main an additional quantity of oxygen 
in the veffel ; and I atk, where is it, to be 
found ? They fay inthe ca/x of the iron. 
But I anfwer, that this calx exhibits no 
appearance whatever of its containing 
any oxygen, and the acid attached to it 
yields lefs dephlogifticated air on being 
MontHyty Mac, No, XXIX, 
MUNICATIONS. 
fubjected to a red heat, than the fame 
quantity of the acid that was employed. 
in the procefs. And if this calx be af- 
terwards expofed to the heat of a burning 
lens in atmofpheric air, it is fo far from 
making any addition to it, that this air 
is diminifhed. 
It is acknowledged by my opponents, 
that after the folution, the acid in the vef= 
fel will not faturate more alkali than it 
would have done before. Since, then, this 
additional quantity of oxygen which the 
new theory fuppofes, cannot be founds 
either in the form cf an acid, or of de- 
phlogifticated air, what evidence is there 
of its exiftence? And is not the proba- 
bility greatly in favour of the inflammas 
ble air coming from the iron rather than 
from the water, and that by the lofs of 
this principle it becomes a calx. If this 
be the cafe, metals are compound fub- 
fiances, and water, as far as we yet know, 
a fimple one; whereas, according to the 
new theory, metals are fimple fubitances, 
and water the compound. 
2. When fteam is applied to red hot 
iron, inflammable air is procured, and the 
iron receives an addition of about one half 
of its: former weight, and is the fame 
thing with what the forge-men in England 
call jixery cinder, and with the fcales of 
von in a blackf{mith’s fhop. This fub- 
ftance the antiphlogiftians iay is an oxyde 
of trap, TTBPOnDE, that the water is de- 
compoled by paffing in contact with it, 
whenjthe hydrogen is feparated in the forma 
of inflammable air, and the oxygen re- 
mains united to it. But TI afk, what is 
the evidence of this fubftance containing 
any oxygen, when it can neither be re= 
duced to an acid, nor exhibited. in the 
form of oxygenous gas, or dephlogifti- 
cated air? I think that the addition to 
the iron Y mere water, and when it is 
heated in inflammable air, the iron is rée- 
vived, and the water fet at liberty. > 
Ancther evidence of a folid fubftance, 
like this, containing oxygen, is its oxy- 
genating, or as I call.it, dephlogiftica- 
ting, the marine acid. But though this 
4 — fubfkance 
