That is really special! How nice that it stayed in your family.
My oldest is from 1830, A history of the state of New York, from the first discovery of the country to the present time: With a geographical account of the country and a View of its original inhabitants. And it was given to me as a gift by a Doper who came across it and knew I liked New York state history.
We have a first edition of “Life on the Mississippi” by Mark Twain. It’s in crappy condition. Also Tennyson’s “Idylls of the King,” but I can’t find it now.
Rogers, Samuel The Poetical Works of Samuel Rogers, Thomas Campbell, James Montgomery, Charles Lamb, and Henry Kirke White 1845
Yonge, Charlotte M. A Book of Good Deeds 1864
Cowper, William The Poetical Works of William Cowper (The Lansdowne Poets) c. 1880?
[includes his 1774
“God moves in a mysterious way
His wonders to perform;
He plants His footsteps in the sea
And rides upon the storm.” etc.]
Harlan, Marion et alii Young People’s New Pictorial Library of Poetry and Prose (w/425 engravings) [has (reprint?) page from NY Herald 4/15/1865 re Lincoln Assassination; class photo kids] 1888
I think my oldest is a 1920’s edition of Twilight of the Gods by Richard Garnett, a sort gift book edition with gold edges,
You know, if you just want to read the books, or even just look at them, the internet has made that almost too simple. When I was young two of my favorite books were collections of Sam Loyd puzzles edited by Martin Gardner. He constantly would refer to Loyd’s Cyclopedia as his source, but that book was long out of print and unobtainable. Until a few years ago. The illustrations are a hoot. And off color.
I have a six volume set of the History of the Jews by Graetz that was published in the 1890s. It was given to me by my Mom’s first cousin because his kid didn’t want it. It probably originally belonged to his grandfather/my great grand father.
ETA: This guy: Heinrich Graetz - Wikipedia. I just googled it for the first time. It’s actually a well known scholarly work that was published in German in the 1860s. I have the first English translation.
Somewhere I have an astronomy book from ~1910. Highlights include:
The Sun is on the order of tens of millions of years old and the heat is caused by the gravitational compression of it’s gasses. It will continue to burn for another 10 million years. (Nuclear fusion was unknown at the time.)
The Milky Way galaxy is the extent of the known Universe. It is debated what lies beyond, if anything. (Galaxies were believed to be a type of spiral nebula within our own galaxy at the time.)
Mars has a water cycle as evidenced by seasonal variations visible in vegetation growth. The canals are vegetation-lined waterways and it is debated whether these are natural rivers or artificial irrigation channels. Venus may also have vast oceans of water because the surface is continuously obscured by cloud cover.
My mother has a family bible that is quite old. I don’t know how far back it goes, but it’s pretty far - one of the names in it is Meriwether Lewis.
Personally, I think the oldest book on my shelves is a 1945 Emily Post.
I have a book from 1893, published by the sponsor of that year’s World’s Fair, that records in loving detail every single exhibit.
It’s cool for me because I own a grandfather’s clock, a family heirloom handed down for several generations, that won a prize at that fair.
The book was given to me by a cousin fairly recently, as she knew I had the related clock and figured the book and the clock belonged together. (The brothers and sisters involved in the debacle have long since passed away, but my mother “stole” the clock when my grandmother died; all 5 siblings wanted it so while the others were discussing it, my mother and father ran off, got a truck, and absconded with the clock, effectively ending the argument. The siblings held it against her for years!)
Anyway, I knew the story of the clock winning a World’s Fair prize and how my mother grabbed it, but what I did NOT know until my cousin passed on the book was which World Fair it was. As it happened, when my cousin sent me the book I had just finished reading “The Devil in the White City” (a fascinating factual account of the fair and a serial killer who operated during it).
So now, thanks to the book, I know that a serial murderer spent a lot of time in close proximity to my clock. For all I know he scoped out a victim while she was admiring it. :eek::eek::eek:
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Our family Bible is dated 1885.
What I have in this line, is pretty weak sauce compared with books told of by many posters in this thread: but my reckoned “joint oldest”, passed down in the family, are, best guess, from about the World War 1 era (no publication date shown in either). They are: a delightfully illustrated edition of the “Uncle Remus” stories (I fear that I find making sense of Joel Chandler Harris’s Southern Black dialect, more of a labour than I’m prepared to undertake; but the pictures are lovely); and a little book of “Sixty Best Humorous Recitations” – the majority of them cringe-makingly un-funny and awful.
My oldest is the 2-volume 1st edition of Tales of the Hall by George Crabbe, published in 1819, and bought by me in 1965. Unfortunately, I have got around to reading it yet.
That’s a great story!
My two oldest books are Roads of Destiny and The Gentle Grafter, both by O.Henry. Part of a six book set, they’re from 1916. I picked them up at a Salvation Army for about seventy-five cents each. I love O.Henry and have all his short stories across multiple books, but I couldn’t pass these two up.
I have six leather-bound O Henry books (all collections of stories) from 1913, including those two. I originally found 5 in pretty good condition in a used book store, and I have no idea what I paid for them. Later I was searching for the rest of the series (there are 12 in all) online, and they are pretty hard to find for sale. I did find one and bought it, but it was not in as good condition as the original 5. Every so often I look again for the other volumes, but no glory so far. I also have a pretty pedestrian complete set of Oscar Wilde from Doubleday, 1923. Some of them are pretty good, some are not very good at all.
“LibraryThing”? I have checked this out. It looks very useful!
That’s an awesome story to go with the book. You should write it down and keep it in the front of the book, so whoever ends up with the book knows the story.
Poems and tales of Edgar Allan Poe by Alphonso G Newcomer
1899
Publisher: Scott, Foresman and Company.
Its getting old but in good shape otherwise. Interesting little book! 
It’s just a baby in terms of this thread, but my oldest book is a 1944 issue of The Bluejackets’ Manual from when my maternal grandfather joined the Navy.
A combination cookbook / household manual from the 1820’s (I don’t remember the title or exact date, and I have it boxed up, so I can’t easily check them, sorry…). It’s in terrible condition, and full of recipes which are alternately delicious-sounding and awful-sounding, plus the household sections has a lot of very questionable and occasionally outright dangerous medical advice.
Next oldest would be some pattern sheets from French fashion magazines of the 1840’s; I collect early 20th century magazines with pattern sheets, and these came as part of a lot. I don’t care about the era, so I should probably sell them…
I have one of these, but it’s a young whippersnapper compared to yours - it was published in 1907. It’s called The Compendium of EveryDay Wants and it makes for utterly fascinating reading. There are sections devoted to etiquette, civic responsibility, legal matters, veterinary medicine, home chemistry, and all sorts of other goodies.
This isn’t the same edition I have, but it looks to be pretty damned close.
I actually have several of that kind of book over the ages; I don’t have that particular one, but it looks pretty awesome. 
That class of books was published up into the 1930’s at least, and what makes it fun to have a selection is that, especially for the more cheaply-produced ones, they all crib content directly from previous generations, and you can watch inaccuracies and oversimplifications creep into the extracts over time.* Particularly dangerous in the case of aforesaid medical advice. Some of the recipes for cosmetics/toiletries could also get you into serious trouble.