- Cruise Travel Magazine: Currently, there are issues from 1970 on.
- Popular Science Monthly: Currently, there are issues from 1870 on. Check out the article by Harry Fielding Reid from Jan. 1910, "How could an explorer find the pole?" or the articles on the centenary of Darwin's birth that speculate on his place in future biology in the same issue.
Searching is via the usual Google Books interface, books.google.com, and when you retrieve a magazine article, the screen will often say things like, "Read this book." There is searching help available just for the magazines, which says:
Once you've found a magazine that interests you, you can browse other issues of that magazine from the "About this magazine" page. Click on the "About this magazine" link at the top left of the screen, and scroll down to the section marked "Browse all issues." You can then explore different issues of the magazine by clicking on a decade that interests you, and then scrolling through the individual issues from that time.
However I didn't find the "Browse all issues" displayed consistently--perhaps Google's not sure which "books" are "magazines."