Read it through once

Here would be the place to mention how an army encamped upon the Pampas finds itself next morning imprisoned and doomed to perish miserably in a forest of giant thistles which has sprung up during the night. There is no doubt that thistles and other weeds are very tall in both South and North America. Fennels are ten to twelve feet high, and even little Chenopodiums (such as in England may reach eighteen inches), become in South America seven to eight feet high, but the tallness of some of the stories is more remarkable even than that of the plants!