When Edward Gibbon was writing about the fall of the Roman Empire in the late 18th century, he could argue that transportation hadn’t changed since ancient times. An imperial messenger on the Roman roads could get from Rome to London even faster in A.D. 100 than in 1750. But by 1850, and even more obviously today, all of that has changed.
One layer was certainly 17th century. The 18th century in him is obvious. There was the 19th century, and a large slice, of course, of the 20th century; and another, curious layer which may possibly have been the 21st.