Note 39 — Chapter IX · COMPOUNDS OF CARBON WITH OXYGEN AND NITROGEN
George Kamensky translation
Urea is undoubtedly a product of the oxidation of complex nitrogenous matters (albumin) of the animal body. It is found in the blood. It is absorbed from the blood by the kidneys. A man excretes about 30 grams of urea per day. As a derivative of carbonic anhydride, into which it is readily converted, urea is in a sense a product of oxidation.