Diary of John Quincy Adams, volume 1
This morning at 4 o'clock we set off from Naumburg for Leipsic where we arriv'd at about 11 o'clock A.M. The distance is about 36 Miles. The first post was a little mountainous but pretty well cultivated, the last post is a large plain well cultivated also.
A German Post Mile is 6 English Miles And a German post is generally two German Miles; You pay a German Guilder per post for each horse; for a post and a half you pay a guilder and a half per horse and for two posts in proportion. A German Guilder is about 1 shilling and 10 pence Sterling. The money changes in almost every petty prince's dominions and the same silver money does not pass above 100 Engh. Miles, in general, but French Guineas or Dutch Ducats pass all over Germany. In some places Ducats are better than Louis D'ors, and in others L'D'or's are better than Ducats, but you lose something by either, in the Exchange.