Grice and Priestley on the phlogiston ("Considerations on the theory of the phlogiston, and the decomposition of water"

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What's wrong with the deliverance of 'phlogiston theory', as cited by Grice?

As wiki illustrates us,

"Phlogiston theory (from φλογιστόν, "burning up", from φλόξ "fire") was stated in 1667 by Becher. "A defunct scientific theory that posited the existence of a fire-like element ... contained within combustible bodies, and released during combustion."

Quod erat demonstrandum. "Phlogiston theory is an attempt to explain processes such as combustion and the rusting of metals, which are now understood as oxidation.'

'In 1667, Becher published his "Physics".'

"Traditionally, alchemists considered that there were 4 elements."

1. fire
2. water
3. air,
4. earth.

"In his Physics, Becher eliminates fire and air and replaces them with 3 forms of 'earth'

1. water
2. earth
----- 2. 1. terra lapidea,
----- 2. 2. terra fluida, and
----- 2. 3. terra pinguis.

[1][2]

"Terra pinguis was the element which imparted oily, sulphurous, or combustible properties.[3]"

"Becher believes that terra pinguis was the key feature of combustion and is released when combustible substances are burned.[1]"

"In 1703 Stahl, professor of Medicine at Halle, proposes a variant, and renames "terra pinguis" as "phlogiston".

Becher's and Stahl's theory is the attempt to explain oxidation processes such as fire and rust."

"The theory holds that all flammable materials contain phlogiston."

"Phlogiston is a substance without colour, odor, taste, or mass. It is liberated in burning. Once burned, the "dephlogisticated" substance is held to be in its "true" form, the calx."

"Phlogisticated substances are those that contain phlogiston and get are "dephlogisticated" when burned."

"Substances that burn in air are rich in phlogiston."

"The fact that combustion soon ceases in an enclosed space is evidence that air has the capacity to absorb only a definite amount of phlogiston."

"When air becomes phlogisticated it no longer serves to support combustion of any material." "Nor would a metal heated in it yield a calx; nor could phlogisticated air support life, for the role of air in respiration was to remove the phlogiston from the body."[5]

"Phlogiston is anti-oxygen in today's terms."

"Joseph Black's student Daniel Rutherford discovered nitrogen in 1772 and the pair used the theory to explain his results. The residue of air left after burning, in fact a mixture of nitrogen and carbon dioxide, was sometimes referred to as "phlogisticated air", having taken up all of the phlogiston."

"Conversely, when oxygen was first discovered it was thought to be "dephlogisticated air", capable of combining with more phlogiston and thus supporting combustion for longer than ordinary air.[6]"

"Eventually, quantitative experiments revealed
problems"

E.g. "Some metals, such as magnesium, gain weight when they
burned, even though they were supposed to have lost phlogiston."

"However, Lomonosov attempts to repeat Boyle's celebrated experimentin 1753 and concludes that phlogiston theory is false."


"Today", he wrote in his Diary, "I made an experiment in hermetic glass vessels in order to determine whether the mass of metals increases from the action of pure heat. The experiment demonstrated that the famous Boyle was deluded, for without access of air from outside, the mass of the burnt metal remains the same."

The wiki also teaches us:

"Some phlogiston proponents explain Lomonosov's counterexample by concluding that phlogiston has negative weight."

"Louis-Bernard Guyton de Morveau gives the more conventional argument that it was lighter than air."

"However, an analysis based on the Archimedean principle and the densities of magnesium and its combustion product shows that just being lighter than air cannot account for the increase in mass."

"Still, phlogiston remained the dominant theory until Lavoisier shows that combustion requires a gas that has weight (oxygen) and could be measured by means of weighing closed vessels."

"The use of closed vessels also negates the buoyancy which disguises the weight of the gases of combustion."

"Lavoisier's observations solve the weight paradox and set the stage for the new caloric theory of combustion."

"During the eighteenth century, as it became clear that metals gained weight when they were oxidized, phlogiston was increasingly regarded as a principle rather than a material substance.[7]"

"By the end of the eighteenth century, for the few chemists who still used the term phlogiston, the concept was linked to hydrogen."

"Priestley, e.g., in referring to the reaction of steam on iron, whilst fully acknowledging that the iron gains weight as it grabs oxygen to form a calx, iron oxide, iron also loses

“the basis of inflammable air (hydrogen), and this is the substance or principle, to which we give the name phlogiston.”[8]

"Following Lavoisier’s description of oxygen as the oxidizing principle (hence the name oxygen: oxus = sharp, acid; geneo = I beget), Priestley describes phlogiston as the alkaline principle.[9]"

"Phlogiston theory is the opposite of "Oxygen theory"."

"Phlogiston theory states that all flammable materials contain phlogiston that is liberated in burning, leaving the "dephlogisticated" substance in its "true" calx form."

"In oxygen theory, on the other hand, flammable materials (and unrusted metals) are "deoxygenated" when in their pure form and become oxygenated when burned."

"However, the first part of the old theory requires that phlogiston has weight (since ashes weigh less), but the second requires that it have no weight or negative weight, since corroded metals weigh the same or more, depending on whether or not they are allowed to corrode in sealed chambers."

"Phlogiston theory allows chemists to bring explanation of apparently different phenomena into a coherent structure."

These are:

1. combustion,
2. metabolism, and
3. formation of rust.

"The recognition of the relation between combustion and metabolism was a forerunner of the recognition that the metabolism of living creatures and combustion can be understood in terms of fundamentally related chemical processes."

Refs:

Becher, Physica Subterranea.
J. Conant, ed. The Overthrow of Phlogiston Theory: The Chemical Revolution of 1775–1789. Cambridge: Harvard University Press (1950), 14.
For a discussion of how the term phlogiston was understood during the eighteenth century, see: J. Partington & D. McKie; “Historical studies on the phlogiston theory;” Annals of Science, 1937, 2, 361-404; 1938, 3, 1-58; and 337-71; 1939, 5, 113-49.
Joseph Priestley; Considerations on the doctrine of phlogiston, and the decomposition of water; P1796; p.26.