How does alcohol (EtOH, methanol) dehydrate tissue in culture?

Tissue slides are placed in increasingly high concentrations of alcohol to dehydrate them before fixation. What is the process by which this dehydration occurs? (Mechanisms, websites, all good.)

Thanks!

PS: I'm *not* asking about how the alcohol dehydrates the body (by suppressing production of ADH/vasopressin)

PPS: I'm *not* asking about 'alcohol dehydration,' where an alcohol reacts to form a water and an alkene, etc.

Answer:
Le Chatelier's Principle: When a stress is brought to bear on a system in equulbirum, the equlibirium shifts to relieve the strain. By mass action, if the concentration of water is larger in the tissue than in the surrounding medium, water flows out of tissue into medium. Alcohol correspondingly flows in.

Embedding media are compatible with alcohols but fog with water. Surface tension and capillarity distorts water-drying speciments. Alcohol has a much lower surface tension so capillary forces are correspondingly lower.

Freeze drying and critical point drying are alternatives. Solvent dehydration is cheap, fast, and easy while adequately retaining specimen structure.
Mass transfer.

Water exits the cell and alcohol enters the cell so that an equilibrium concentration is attained both inside and outside the cell.

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