"Some minds improve by travel, others, rather, resemble copper wire, or brass, which get the narrower by going farther"

In this quote, Thomas Hood is comparing the effect of travel on various kinds of minds. He suggests that for some people, traveling can cause personal development and improvement of their minds. Nevertheless, for others, the reverse might be true. Hood utilizes the example of copper wire or brass, which become narrower as they are extended. Similarly, he indicates that for some people, the more they travel and experience brand-new things, the more narrow-minded they end up being. This quote highlights the concept that the impact of travel on one's mind is not universal and can vary considerably from person to person.