Hell if I know...
Glycol is basically Antifreeze...as is used in automobiles.
It seems that glycol CAN freeze, but it's freezing point is lower than that of water.
And if you mix glycol with water it lowers the freezing point much more.
At least this is true with ethylene glycol.
From Wikipedia:
https://en.wikipedia.org/wiki/Ethylene_glycol
Pure ethylene glycol freezes at about −12 °C (10.4 °F) but, when mixed with water, the mixture freezes at a lower temperature. For example, a mixture of 60% ethylene glycol and 40% water freezes at −45 °C (−49 °F).[4] Diethylene glycol behaves similarly. The freezing point depression of some mixtures can be explained as a colligative property of solutions but, in highly-concentrated mixtures such as the example, deviations from ideal solution behavior are expected due to the influence of intermolecular forces.
There is a difference in the mixing ratio, depending on whether it is ethylene glycol or propylene glycol. For ethylene glycol, the mixing ratios are typically 30/70 and 35/65, whereas the propylene glycol mixing ratios are typically 35/65 and 40/60. It is important that the mixture is frost-proof at the lowest operating temperature.[17] ‹See Tfd›(in Danish)
Because of the depressed freezing temperatures, ethylene glycol is used as a de-icing fluid for windshields and aircraft, as an antifreeze in automobile engines, and as a component of vitrification (anticrystallization) mixtures for low-temperature preservation of biological tissues and organs. Mixture of ethylene glycol and water can also be chemically termed as glycol concentrate/compound/mixture/solution.
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I'm sure that Dr. Hubbard had a good reason for
not explaining exactly why a thetan which is not part of the physical universe would freeze when utilizing this mixture of physical universe substances.
It could cause severe restimulation of Incident II, giving you pneumonia or just killing you instantly.
Or more likely, it could cause you to stop breathing because you can't stop laughing so hard.