Echoing these great difficulties in chronological notations, D. MacNaughton wrote: "Systems of ancient chronology, propounded even since the days of George Smith, have been many and various, and while in one year one date is assigned with an air of finality to a certain king, a few years later the date is abandoned as erroneous. These changes are natural." In fact, it has taken many hundreds of years for scholars to arrive at the dates that are now assumed to be accurate, as purported by Grafton in his book on "Joseph Scaliger," and where he shows how long it took for Roman consular dates (and archon dates, etc.) to be converted into BC/AD. All the ancient dating systems had to be aligned and converted into the modern system, and cross-referenced, and where others were not easily translatable.
