Google has put together a search engine (at http://news.google.com/archivesearch) that allows you to search through historical archives of newspapers, magazines, and other historical sources going back as far as 200 years.
You can get results sorted both by relevance and by a timeline, showing oldest hits first, and the results will often link to a way to purchase the article from the original source. The fact that these archives were typically hidden from normal Google spiders because they are available only via a purchase is the reason why Google did not link to these articles before, and now you will be able to search for various articles from a single source rather than having to go to various periodical sources to conduct searches. The best part of all is that the search engine is accessible for people who use screen reading technology.
Click this link to visit the Google News Archive Search Engine at http://news.google.com/archivesearch.