"The Lectures as begun in 1827 included ordinary Mechanics, ordinary Hydrostatics and Pneumatics (I think that I did not touch, or touched very lightly, on the subjects connected with the Hydraulic Ram), and ordinary Optics (with a very few words on Polarization and Depolarization).

In 1830 I believe I went (in addition to what is mentioned above) into Polarization and Depolarization of all kinds.

I heard an admirable depolarization of the story of the young man who "had great possessions" from the Rev. Mr. H. in another pulpit, and felt that I had never half understood it before.

All paraphrases are more or less perfect depolarizations.