It's nice to meet a knowledgeable person. Molecules are polar and nonpolar. Non-polar ones do not have electric poles. Polar molecules have electric polarity (+) and (-). So a polar molecule can be stretched by an electric field. The water molecule is polar and in the Meyer generator was stretched by an electric field. The strength of the electric field is greater than the strength of the covalent bond. This physical principle is embedded in the Meyer generator.