Just about any book written in or before 1923 is in the public domain (and, by the way, works created by the federal government are in the public domain, too.) There are many reasons to consider using these treasures. They were written at a time when God and Christian values were more honored in the general culture; they reflect these values, even include reference to God in their content. If they have endured they are likely good reading, maybe because of writing style or historically important information; some are truly classics. At the very least, they are free to download or inexpensive to buy (usually.)
Project Gutenberg is the first and now most extensive source of electronic books (ebooks.) Many other sites get their ebooks from it. You can search by author, title, or subject, which is good if you know what you are looking for, but you can't really browse. For example, Eva March Tappan's book, Diggers in the Earth, which I found through another web site, is listed under subject:reader, which I never would have guessed. While they have greatly shortened the very annoying legalese at the beginning of their books, this is not so of many of the ebooks they first published. That can all be easily deleted unless you are downloading the ebook for your PDA.
Manybooks takes books from Project Gutenberg and converts them into a wide variety of formats for PDAs and Smartphones, even for the new Amazon Kidle. Not only can you search by author and title, you can also browse by category. (I only wish I could limit the choices by selecting books that have two or more categories.) When you view a title, it will also provide a link to Librivox if the title is available in audio.
The Baldwin Online Children's Literature Project is another great site that is independent of Project Gutenberg, so it has many titles not available elsewhere on the web. The books are nicely categorized to make browsing easy. Unfortunately you cannot easily download any of the titles since the site is linked to Yesterday's Classics, a separate site where you can purchase paperback reprints of many of the titles.
Google has been scanning the book holdings of many academic institutions and making these ebooks available at Google Books. The site is so enormous that you really cannot browse it; you need to know what author or title you're looking for. Most of the books that are out of copyright, and some that are still in copyright, can be viewed and downloaded in pdf format. You can even do a full text search of books for which text is available to download.The Internet Archive text section also has a vast number of books not found at either Google or Project Gutenberg. Their Americana collection contains almost 200,000 books from libraries around the country scanned by Microsoft, Yahoo, and the Sloan Foundation. The search feature is very good at narrowing subjects, though you can only truly browse by author or title. Thanks, Christi, for prompting me to take another look at the site!
Buying old books can be a bit tricky when one person's "good" condition may be another's "poor." In general, though, I have had very good experiences with it. I have been satisfied with the vast majority of books I have bought, I've even been impressed by some. On rare occasion have I not been happy with what I had purchased, and only once have I not been satisfied with how the seller wanted to resolve the dispute. I buy the vast majority of my used books from 4 places.
- Library book sales. Most children's titles are $0.25 to $1.00 depending on the sale. I use Book Sale Finder to find out when they are happening in my area.
- Abebooks. No book is less than $1 but shipping varies by seller, and many have discounted shipping for multiple books. I have used the aggregate used book engines like AddALL and Bookfinder, but abebooks usually has the best price.
- Amazon. Many books sell for less than $1 but shipping is never less than $3.99 nor will you get a shipping discount for multiple books.
- Used book stores. I have one I really like about 30 minutes from my house. Nothing is catalogued; he does not do Internet sales. It is a real adventure in serendipity!
In lurking around these sources, I have found some interesting children's science titles you may want to look at yourself. Keep in mind I have not read most of these—yet!
The Baldwin Project has three Ambleside Online titles: Madam How and Lady Why by Charles Kingsley, The Fairly Land of Science by Arabella Buckley, and Great Inventors and Their Inventions by Frank P. Bachman. They also have works by Jean Henri Fabre and Charles Gibson; search by genre and scroll down to "Science" to see the titles.
I prefer to browse Manybooks.net to get an idea of what is available at Project Gutenberg. A few gems include Country Walks of a Naturalist with His Children by W. Houghton, Diggers in the Earth by Eva Marie Tappan, Rollo's Experiments by Jacob Abbott, and a whole series of invention and industry titles like The Story of Glass, Carl and the Cotton Gin, and several others by Sara Ware Bassett. You can subscribe to RSS feeds for new titles in each category at Manybooks.
Please add comments if you have any treasured places to find old books, and any title recommendations you have.