It’s mocking the conspiracy crowd who believe the secret overlords are mind-controlling the sheeple with chemicals released by jet airplanes.
The comic is a bit off-base, though, as visible “chem trails” are water vapor, not jet engine fumes.
I think CIDU Bill is complaining that there’s usually some kind of pun with Wiley’s dictionary, and this just seems to be a simple statement.
Something more in line would be, “Chem Trails – “the only trails that end in deposits of tinfoil” or something like that.
And since “tinfoil” in modern times has been made from aluminum, the misidentification of chem trails is fitting too.
“The comic is a bit off-base, though, as visible ‘chem trails’ are water vapor, not jet engine fumes.”
“Vapor” and “fumes” are functionally identical, and the contrails form because the jet engine warms the air as it operates.
Also, of course, some jet engines do produce smoke. The venerable F4 fighter was well known for smoking.
There is a pun here, isn’t there? The long vapour trails left by planes are called ‘contrails’. The word looked up is ‘chem trails’, and as pointed out by BTWW this is jab at those who believe that the gov’t (or a secret cabal, or the tooth fairy, or whoever) is poisoning the atmosphere with chemicals via airplanes. Contrails vs chem trails. Geddit?
James Pollock- fumes are fine particulate matter usually the result of combustion (e.g., smoke) where vapors are gaseous matter created by changes in temperature and or pressure. (e.g., steam)
Blinky, the dictionary doesn’t agree with you.
” noun
1.
Often, fumes. any smokelike or vaporous exhalation from matter or substances, especially of an odorous or harmful nature:”
Apparently, the word traces back to Latin, from a word that meant smoke or steam.
First time in a long time I actually got a laff out of B.C.
James Polack- Perhaps it’s because I work in the air pollution control community, but there is definitely a difference between fumes and vapors, both legally and scientifically,
James Pollock- sorry about misspelling your name- no disrespect intended.
“Perhaps it’s because I work in the air pollution control community…”
To people who don’t, however (which is most of us)…
A car that is down to no more liquid in the fuel tank, forever, is said to be “running on fumes”. I would suggest that this is one of the, if not THE, most frequently-used context for the word “fumes”.
Properly contrails. Some say chem trails. I get a kick out of calling them jet tracks.
Comics I Don't Understand 
It’s mocking the conspiracy crowd who believe the secret overlords are mind-controlling the sheeple with chemicals released by jet airplanes.
The comic is a bit off-base, though, as visible “chem trails” are water vapor, not jet engine fumes.
I think CIDU Bill is complaining that there’s usually some kind of pun with Wiley’s dictionary, and this just seems to be a simple statement.
Something more in line would be, “Chem Trails – “the only trails that end in deposits of tinfoil” or something like that.
And since “tinfoil” in modern times has been made from aluminum, the misidentification of chem trails is fitting too.
“The comic is a bit off-base, though, as visible ‘chem trails’ are water vapor, not jet engine fumes.”
“Vapor” and “fumes” are functionally identical, and the contrails form because the jet engine warms the air as it operates.
Also, of course, some jet engines do produce smoke. The venerable F4 fighter was well known for smoking.
There is a pun here, isn’t there? The long vapour trails left by planes are called ‘contrails’. The word looked up is ‘chem trails’, and as pointed out by BTWW this is jab at those who believe that the gov’t (or a secret cabal, or the tooth fairy, or whoever) is poisoning the atmosphere with chemicals via airplanes. Contrails vs chem trails. Geddit?
It’s a very complex issue. To fully understand it, there is this very informative, and in no way crazy, video on YouTube. https://www.youtube.com/watch?v=vca7c04r95I
Of course, there’s an XKCD for that:
https://www.xkcd.com/966/
Actually, there are at least two:
https://xkcd.com/1677/
James Pollock- fumes are fine particulate matter usually the result of combustion (e.g., smoke) where vapors are gaseous matter created by changes in temperature and or pressure. (e.g., steam)
Blinky, the dictionary doesn’t agree with you.
” noun
1.
Often, fumes. any smokelike or vaporous exhalation from matter or substances, especially of an odorous or harmful nature:”
Apparently, the word traces back to Latin, from a word that meant smoke or steam.
First time in a long time I actually got a laff out of B.C.
James Polack- Perhaps it’s because I work in the air pollution control community, but there is definitely a difference between fumes and vapors, both legally and scientifically,
James Pollock- sorry about misspelling your name- no disrespect intended.
“Perhaps it’s because I work in the air pollution control community…”
To people who don’t, however (which is most of us)…
A car that is down to no more liquid in the fuel tank, forever, is said to be “running on fumes”. I would suggest that this is one of the, if not THE, most frequently-used context for the word “fumes”.
Properly contrails. Some say chem trails. I get a kick out of calling them jet tracks.