Digital Palimpsest

One of the greatest artifacts of Ancient Greek literature is the Archimedes Palimpsest. It seems to be a typical prayer book from Medieval times, bound up in parchment. But in faint text, underneath the illuminated icons and poetic text: lies the only extant Greek copy of the lost books of Archimedes.

Perhaps there is a parallel for modern digital and online history. There's something within the complicated system of a computer that holds records that are meant to be forgotten. If we could recover that data... we might be able to make incredible discoveries, and resurrect snapshots of sites that may no longer be extant.

Web Caches

The most obvious digital palimpsest is the Web Caches on your computer. These large stores of random images and HTML are a complete log of all the websites you've seen.

The most valuable web caches come from browsers that you haven't used in a while. Or that you used to use a lot, but have now put in storage.

Chrome

1. Go to chrome://cache in your browser. Wait for it to load, it can take a while.
2. Use Ctrl-F to find the website you want to recover. Click on it to open a new tab.
3. Enter the cached tab (with all the hexadecimal data), right-click on it and choose Save as.

After you obtain the cache file you want, you can just upload it to this Javascript app and it will convert a Chrome cache file into a readable HTML file. (it doesn't upload to a server, your browser does all the work). Just unzip the .gz file using 7zip, and be amazed.

Firefox

about:cache

Mobile Apps

The smartphone age adds a new vector of information: mobile apps. Especially 4chan apps, which leave behind some cached threads and thumbnails that can last for quite a while.

Android Webkit Browsers

The Android Webkit browser (at least the ones after ICS) have the ability to check threads via about:cache.

Android Chrome Browser

With the Android Chrome Browser, you can just go to chrome://cache, tap the menu button, and use Find to look for the right URL.

The real problem though, is how to extract and view such cache files. For some reason, it shows you the binary file in pure hexadecimal rather than a preview. However, it does this to preserve all media on the webpage in one nice file, HTML and images and all. You need to send this cache file to a computer for further processing.

There are two methods to grab the cache file:

• Select the entire page, copy it, and send it via Gmail to yourself. Unfortunately, the Android clipboard has a text limit, so this might not be practical for large pages.
• Use Chrome's Remote Debugging Feature to grab the webpage. You'll need to enable USB Debugging on your phone for Chrome to recognize it. Once you have it set up, you will be able to interact with the tabs on your phone.
  1. Using your phone, go to chrome://cache, then open the cached page to recover.
  2. Next, via your computer, click Inspect on that cached page tab. A small window will pop up, click the Sources tab. Now right-click the cache file, and click "Save As".

After you obtain the cache file you want, you can just upload it to this Javascript app and it will convert a Chrome cache file into a readable HTML file. (it doesn't upload to a server, your browser does all the work). Just unzip the .gz file using 7zip, and be amazed.