[Illustration: Figure 22.--ARTHUR KORNBERG (b. 1918) AND SEVERO OCHOA (b. 1905) shared the Nobel Prize in Medicine and Physiology in 1959. Kornberg received it for research on the biological synthesis of deoxyribonucleic acid. In particular, he found that four triphosphate components and a small amount of the end product as a "template" had to be present for the enzymatic synthesis. Ochoa received his share of the prize for research in ribonucleic acid and deoxyribonucleic acid. In particular, Ochoa synthesized polyribonucleotides and used the radioactive isotope, P^{32}. The synthetic polyribonucleotides were found to resemble the natural substances in all essentials.] Cl H O | | || OCH_{3} | | ||/ Cl--C--C--P Bayer's L 13/59 | | \ (Dipterex) | | OCH_{3} Cl OH (CH_{3})_{2}N O O N(CH_{3})_{2} \|| ||/ P--O--P Schradan / \ (CH_{3})_{2}N N(CH_{3})_{2} Octamethylpyrophosphoramide [Illustration: Figure 23.--MELVIN CALVIN (b. 1911) received the Nobel Prize in Chemistry in 1961 for his research in photosynthesis, in which he specified the function of phosphoglyceric acid as an intermediate in the synthesis of carbohydrates from carbon dioxide and water by green plants.] The story of phosphorus, which began 300 years ago, has acquired new importance in this century. Many scientists have contributed to it: 13 of them have received Nobel Prizes for work directly bearing on the chemical and biological importance of phosphorus compounds. In chronological order, they are: Eduard Buchner, Albrecht Kossel, Otto Meyerhof, Arthur Harden, Hans von Euler-Chelpin, George de Hevesy, Carl F. Cori, Gerty T. Cori, Fritz Lipmann, Lord Alexander Todd, Arthur Kornberg, Severo Ochoa, and Melvin Calvin. The developers of industrial production and commercial utilization of phosphate compounds have had other rewards. Some impression of the continuing growth in this field[43] can be gained from the following data. PHOSPHATE ROCK annually "sold or used by producer" in the United States in million long tons (2,240 lbs.) 1880 0.2 1890 0.5 1900 1.5 1910 2.655 1920 4.104 1930 3.926 1940 4.003 1945 5.807 1950 11.114 1955 12.265 1955 (world: about 56) 1960 17.202 1962 19.060 Sources: U.S. Bureau of the Census. _Historical Statistics of the United States 1789-1945_ (1949); _Statistical Abstract of the United States._ ELEMENTAL PHOSPHORUS annually produced in the United States in short tons (2,000 lbs.) 1939 43,000 1944 85,679 1950 153,233 1956 312,200 1958 335,750 1959 366,350 1960 409,096 1961 430,617 1962 451,970 Source: U.S. Department of Commerce. FOOTNOTES: