The substance is her Magnum Opus, On the circumstances affecting the Heat of the Sun's Rays (side note: she appears to be part of a scientific family; her husband's somewhat longer paper on a similar subject preceeds hers in the same volume). She takes two jars, with thermometers in each, and exposes them to the sun, having done different things to each. Firstly, one has condensed air; in the other it is exhausted. It gets warmer in the condensed one. She concludes:
Second, dry air didn't get as hot as damp air. Third, the one filled with CO2 got hotter than the one filled with common air (as she herself says, she had no way of assessing the pressures in the vessels, so there are uncertainties in all this). Oddly, despite tabulating 120 degrees (unspecified units) for CO2 and for damp air, she then claims that CO2 was the hottest, at 125. I don't quite understand that.
What did Foote actually see? Not the GHE, but most people seem uninterested by this. TP quotes Katherine Heyhoe: Due to the rudimentary set-up of the experiment, Foote “wasn’t measuring what she thought she was measuring, but she actually serendipitously ended up with an understanding that is correct today,” Which is very delicate, but completely side-steps the point, and not I think entirely true2. AFAIK the only person to even look is good ol' Eli; amusingly, TP provides a link to Eli under the misleading text that EF's work was "not definitive". From Eli I copy the interesting "why did Foote observed a stronger effect from CO2 than H2O? The answer is that she had a much higher partial pressure of CO2 in her containers than H2O because water vapor is condensible at 25-30 C, about 30 Torr", which I think is (a) comprehensible and (b) a bit of a shame that all the revisionsists couldn't also quote. But for the rest: if you ask me to draw an illustrative diagram of the GHE then I can and have; however even after reading Eli's words I'm rather uncertain what EF actually saw. Never mind; no-one else cares so why should I?
Did EF's work actually have any effect, or was it ignored? One of the Justice Warriors says A few years later, Foote’s findings were reflected in the studies of physicist John Tyndall but notice the deliberately ambiguous words used. It implies to imply that Tyndall was influenced by Foote, but there is no evidence for this1.
Note: this isn't new. It first came up in 2011. I thought it was wrong then.
On reflection, the fuss around EF most closely resembles that around Bob Carter after his death. Not, I stress, that this reflects in any way badly upon EF, but on her puffers. Just that those who puffed Carter as a great scientist had not the slightest interest in his actual work; refer to Cainozoic history of southern New Zealand: An accord between geological observations and plate-tectonic predictions.
1. As he says: “With the exception of the celebrated memoir of M. Pouillet on Solar Radiation through the atmosphere, nothing, so far as I am aware, has been published on the transmission of radiant heat through gaseous bodies,”. Roland Jackson writes The saga of Eunice Foote and John Tyndall which considers the possibilities; I think his most compelling evidence of a lack of connection is that Tyndall didn't start with CO2.
2. KH did better in 2016. But there was less sex around then.
* CLIMATE WARS : THE SALT TALKS.
* On the Principles of Economic Principles