[23] _Food and the Principles of Dietetics._ [24] _Food and the Principles of Dietetics_, by Robert Hutchison, M.D. [25] _Bacteria in Milk and its Products_, by Conn. [26] _Dict. App. Chem._, Thorpe. [27] _Nature_, July 23, 1884. [28] _The Exploration of the Caucasus_, by Duncan W. Freshfield, 1896. [29] Quoted by George M. Sternberg, M.D., LL.D., _Text-Book of Bacteriology_, 1898. [30] _Encyclo. Biblica._ [31] Conn. [32] _Cyclo. of Biblical Lit._, M'Clintock and Strong, and Burckhardt's _Arabia_. [33] _The Indian Medical Gazette_, Sept., 1909, "A New Lactic Acid producing Streptothrix," by Gopal Ch. Chatterjee, M.B. [34] In their studies on Leben in the _Annales de l'Institut Pasteur_ of 1899, Rist and Khoury, in speaking of the amount of lactic acid produced by _Streptobacillus lebenis_ in milk, say "Nous avons mesuré cette acidité dans une culture sur petit lait de vingt-quatre heures; elle était .261 grms. per cent. exprimée en acide lactique," which will make the amount of lactic acid produced in one litre of milk 2.61 grms. The production of this small amount of lactic acid does not tally with the ordinary view of the vigorous lactic-acid-producing power of the bacillus. [35] _Prolongation of Life._ [36] _Prolongation of Life._ [37] An accurate census of Bulgaria is being prepared and will exhibit the cases of long life in that country. [38] See A. Rosam, _Österreichische Molkerei Zeitung_, 15, p. 31. [39] _Revue générale du Lait_, vii., pp. 8 and 9 (letter from Dr. Otakar Laxa of Prague, Bohemia, to the author). [40] _On the Prolongation of Human Life_, by Élie Metchnikoff; also _The Century Magazine_, Nov., 1909, "The Utility of Lactic Microbes," by the same author. [41] _Century Magazine_, Nov., 1909. [42] See _Annals of Dairying in Europe_, by Loudon M. Douglas. [43] Adapted from a report by Robert E. Turnbull, in _Live Stock Journal_. [44] _Facts about Milk_, by R. A. Pearson, B.S., Washington. [45] _Care and Handling of Milk_, Marshall and Wright, Bulletin 221, Michigan, 1904. [46] _Journal of the Royal Society of Arts_, March 6, 1908—"Modern Dairy Practice," by Loudon M. Douglas. [47] Skolotowski, _Wratsch_, 1883 (Russian), from Codwyssozki. [48] Podowyssozki, _Zeitschr. f. diat. u. physik. Therapie_ vol. v., 1901, p. 570. [49] Hammersten, _Jahresb. u. d. Fortsch. d. Tierchem_, 1886, Bd. 16, p. 163. [50] Essaulow, _Dissert. Moscow_, 1895, _Abstr., Koch's Jahresb._, 1895, Bd. 6, p. 222. [51] Kern, _Bulletin Soc. des Naturalistes de Moscow_, 1881, 3, p. 141. [52] Krannhals, _Deutsch. Arch. f. Klin. Med._, 1884, Bd. 35, p. 18. [53] Beijerinck, _Centralbl. Bakt. Par._, 1889, Bd. 6, p. 44. [54] Scholl, _Die Milch_, Wiesbaden, 1891, p. 38. [55] Adametz, _Centralbl. Bakt. Par._, 1889, Bd. 5, p. 116. [56] Freudenreich, _Landw. Jahrb. d. Schweiz._, 1896, vol. x., p. 1.