Very varying answers have been and probably will be given to the question how far back influenza can be traced by different medical historians. We cannot be surprised at this when we observe the indefinite and fragmentary character of the older reports, recorded very often by a single person, and he not a physician. Some historians of repute believe that the epidemic of the year 412 b. c, mentioned by Hippocrates and Livy, was influenza. Others associate certain portions of Thucydides, excepting, of course, the Attic pest, with influenza. It is obviously impossible to interpret as influenza outbreaks the Sicilian infectious camp diseases described by Diodorus, from the mere fact of the terrible devastations caused by these diseases. We pass over also a similar interpretation of the epidemics of the sixth to the tenth century, which were characterized by cough and other catarrhal phenomena, although in these instances of cough epidemics, the Italian fever, there is more likelihood that the disease may have been influenza. A. Hirsch thinks to recognize the first authentic influenza epidemic in the scanty reports of the year 1173 from Italy and France. Zerviani believes the first epidemic occurred in 1239. According to Gluge, the history of the disease dates from the year 1323. More complete accounts exist of the epidemic of 1387, which Schmeich, Haeser, Biermer, Ruhemann, and Gratz describe as the first true influenza epidemic. Thompson, Ziilzer, and O. Seifert are still more cautious, and consider the pandemic of 1510 to have been the first outbreak of influenza.