Shortly after this experience had been gained, it became valuable for understanding the chemical nature of a new substance extracted from a natural organ. This substance was named lecithin by its discoverer, Nicolas Theodore Gobley[27] (1811-1876), because he obtained it from egg yolk (in Greek, _lekidos_). He used ether and alcohol for this extraction. Had he used water and mineral acid instead, he would not have found lecithin, but only its components. As Gobley and, slightly later, Oscar Liebreich (1839-1908), subjected lecithin to treatment with boiling water and acid, they separated it into three parts. One of them was the glycerophosphoric acid of Pelouze, the second was the well-known stearic acid of Chevreul, but the third was somewhat mysterious. This third substance was the same as one previously noticed when nerves had been subjected to an extraction by boiling water and acid and, therefore, called nerve-substance or neurine. Adolf Friedrich Strecker (1822-1871) established the identity of this neurine with a product he had extracted from bile and which went under the name of choline. Adolphe Wurtz (1817-1884) succeeded in synthesizing this substance from ethylene oxide, CH_2.O.CH_2 and trimethylamine N(CH_3)_3.[28] Thus, all three parts were identified, and Strecker put them together to construct a chemical formula for lecithin, glycerophosphoric acid combined with a fatty acid and with choline (a hydrate of neurine). { OH } N { (CH_3)_3 } Choline { C_2H_4O } C_18H_33O_2 } HO } } } PO C_16H_31O_2 } C_3H_5O } Fatty Acids Glycerophosphate \--------v-------/ Lecithin according to Strecker This formula was not quite correct. Richard Willstaetter showed that an internal neutralization takes place between the amino group and the free acidic residue. This is expressed in his lecithin formula of 1918. CH_{2}.O.R | CH_{2}.O.R_2 | | O.CH_{2}.CH_{2} | / \ CH_{2}.O--P=O N(CH_{3})_{3} \ / \---O----/ [Illustration: Lecithin (1918)]