The Timeline begins with the year 1400 near the clubhead, and ends at the present, at the grip.  The Timeline is scaled so that the bottom 4/5 covers the years 1800 to the present.  To travel along the Timeline, click down on the golf ball and roll it to a desired year.  The clubhead will display the date, and an entry will appear.  In addition, the category of the entry will animate (if the Icon Animation Option is enabled) to tell you how to locate it through the Category Icons.  If there are more than one entries for the chosen year, you can travel to the next one by using the "down" arrow key.  You can also use both "up" and "down" arrow keys to travel incrementally along the Timeline.  If there isn't a corresponding entry for the chosen year, the golf ball will automatically roll forward to the next year with an entry.