À Friedrich Engels, 13 octobre 1851

Incidentally, during my recent visits to the library, which I continue to frequent, I have been delving mainly into technology, the history thereof, and agronomy, so that I can form at least some sort of an opinion on the stuff…

If you happen to come upon the following book : Johnston, Notes on North America, 2 vols., 1851, you will find all manner of interesting information in it. For this Johnston is the English Liebig. An atlas of physical geography by “Johnston,” not to be confused with the above, may perhaps be had from one of Manchester’s lending libraries. It is a compilation of all the most recent as well as earlier research in this field.