Are there any illustrations? Old atlases are often worth more as framed color plates than complete books.
“… the 1911 Encyclopedia Britannica, where I get ALL my information…”
Whose catchphrase is that?
Jean-Paul Sartre and Albert Camus would be :dubious: and nauseous if they read that…
As well as Bertrand Russell, they had their most important works published after 1911.
Maybe you are not referring to these guys, but I heard it first as a serious item coming from these yahoos:
(Quote starts at 2:54)
“Sold” listings on eBay don’t go back 9 years. 
wild guess- Dirk Gently?
Agree. I bought a set in a used book store for a dollar when it was 75 years old.
Um, folks, the OP asked this question nine years ago.
Damnit! I had 9 years to jump in with that comment, and still got ninjad!
this is my opinion … so, take it with a grain of salt.
i suggest donating it to a museum … if not that, donate it to the library in a hospital … if not that, donate it to a convalescent home … if not that, someone else who can benefit from the knowledge and resources stored within any volume of worth. if you sell it on e-bay or whatever … schmucks will buy it … and the compendium will be reduced to tatters in less than one generation.
sure … some of the info will be outdated and no longer relevant … but, some may prove both timeless 'n practical 'n enduring. yes … we have the internet now … but, tomorrow when the apocalypse reduces our nations and athenaeums to dust … all that remains will be books. books will be our last heritage … a dying legacy … the event horizon.
well … that’s my take.
Yes, but do you remember in the Time Machine movie when Rod Taylor was brought to the books the Eloi still had? The books were in such dilapidated condition that he was able to turn them into dust by just brushing them with the back of his hand.
Look, I love books. I do all my reading from print books (except on trips). I go to the library weekly, scour used book sales, and buy off the internet. My house has books galore; I stopped counting when I passed 10,000. And I’m a professional writer who has put out several books of my own.
But this is silly. No museum, library, hospital, or convalescent home wants or needs a 1911 Britannica. If the apocalypse arrives, every last bit of information in it will be available in thousands of more recent, more accurate, and less racist volumes. The world is awash in old books, billions of them, more than anybody can care for. If you care about words then see to it that every book is scanned and that the digital form is available in various formats spread widely, rather than in paper form.
And why in the world would you call eBay buyers schmucks? Where is this coming from? I’ve bought hundreds of books off of eBay and they are just as valuable as those bought from a bookstore, new or used.
**Exapno **beat me to it. Pretty much what I was going to say.
In conclusion, you may even have a difficult time just getting someone to take it off your hands.
Cut a big 1911 ACP shaped hole in one of the volumes and include one. Should sell in a heartbeat.
After nine years, the books may have been disposed of somehow.
What can be done with such a set? They’d be fine decorative items in a display where shelfspace, not contents, matters. They could be hollowed out to hide stuff. Local theatre groups and school drama departments likely have impressive-looking books for props, but ask. Country folk used to leave Sears catalogs in the bathroom - those thin pages worked as toilet tissue. A 1911 Britannica could be equally useful besides serving as an ideological statement.
We laboriously schlepped a thrift-shop church organ up to our prior house’s second story but it was too heavy and worthless to haul out when we moved so we called it “installed” and let the buyer deal with it. There’s an answer for the OP (if he’s still alive): move and leave the Britannicas behind. Hidden, if necessary.