Alexander Mackay
Alexander Mackay's biography is difficult to come by, but the text detailing his travels in America in 1849 can be accessed via google books.

Quotations

Here also is to be seen in constant whirl the balance-wheel, such as it is, of the most complicated political machine on earth; and here may be best appreciated the working and the value of the constitution.

on Washington, D.C., Travels in the United States in 1846–1847