Years ago I ran across a children’s novel about two boys who go on a cross-country adventure in -get this- a mechanical elephant that their father built. Now my searches on the Net have turned up several other inquiries about this story; but no one seems to know the title, author, publisher or anything like an ISDN number that might help someone track down a copy of said book.
If anyone on the SDMB can track this down, you’ll be the hero of millions (well, dozens at any rate).
Jules Verne produced a two-part novel in 1881 entitled THE STEAM HOUSE, about British explorers traveling across the Indian subcontinent in a huge steam-powered mechanical elephant named “Behemoth.”
The first book was called THE DEMON OF CAWNPORE, the second was TIGERS AND TRAITORS.
This probably isn’t what you want, but I’m posting it anyway to further muddy the waters, and to show off.
FINALLY FOUND
I’d previously tried using Chat GPT to locate barely remembered stories with no luck. But today I tried it again and hit paydirt:
Hooray! First win for Chat GPT! Glad you found your book.
I just feel disturbed at the thought of an elephant – a dry grassland animal of enormous weight, in the everglades, where I expect it would sink inextricably to the bottom of the endless swamp.
I wish Steve had an electric manatee instead.
24 years later. That’s dedication.
My previous record was 11 years when I finally found a reference for Wagner (Faust’s assistant, not Faust himself) and the homunculus.
replacement for extinct link:
I was drawn in by the thread title, not realizing this was a quarter of a century old (!!). Like Ukulele Ike, my first thought was the Jules Verne novel. I knew it because it was reprinted in two volumes by Ace books in the 1960s, and it was adapted in an issue of Classics Illustrated. I never heard of Frederick W. Keith’s 1957 book, although I’m the right age to have read it, if my library had owned a copy.
The notion of going to all the trouble of building a complex articulated animal to ride or to pull a cart, rather than doing the much more simple thing of having your engine simply drive the cart itself struck me as weird, but it was definitely a 19th century affectation. Long before Verne’s novel (1880), Luis Senarens, writing as “Noname” wrote Frank Reade and his Steam Man of the Plains (1876), this beginning a long series of “Frank Reade” novels about a young inventor that predated “Tom Swift”. But Reade himself was ripping off an earlier dime novel author, Edward S. Ellis, whose Stream Man of the Prairies (1868) seems to have started the genre. (Ellis’ book was republished numerous times through 1904). Senarens, by the way, wrote numerous sequels involving, along other things, a steam-powered horse that pulled a cart. I think that Verne was the first with a steam elephant, though.
All this looks like the unrealistic imaginings of enthusiastic early SF authors. But they were acting in the best SF tradition of building on real technology. Because in 1868 American inventor Zadoc Dederick patented a steam-powered human figure that pulled a cart. And, while you might think that people would see the lunacy in buyilding so complex a mechanism for the task, needlessly complicating things, he had lots of imitators doing the same thing.
https://www.saturdayeveningpost.com/sep-keyword/zadoc-dederick/
https://weirdnj.com/stories/mystery-history/newark-steam-man/
Hey, better late than never. 
If they had only hit upon Jansen's linkage - Wikipedia, we might have seem more mechanical animals actually implemented.
I’ve seen movies of contraptions using his linkage walking along beaches, powered by the wind. I’m not sure how well all those heavily used intricate connections would stand up to heavily powered continuous usage. Easier to just use a wheel and axle.
Oh, I didn’t say they were practical, just that 19th century visions of mechanical transportation would have tried longer and harder to make walkers work before giving up. 
Elephants can swim.
The Okavango in Botswana is an enormous inland delta that turn into a truly giant marsh (double the size of the Everglades), that has elephants. The Sudd swamp (even larger) in Sudan also has elephants.
But can mechanical elephants?
Especially steam-powered ones.
Imagine if William Brunton’s locomotive design from 1813 had caught on. In the early days of railways/railroads, there was a perceived problem with traction on iron rails; the lightweight locos of that period surely would slip and fail to pull anything. Blenkinsop invented the rack-and-pinion method of gaining traction, and Brunton built a pair of legs to literally walk along the ground pulling the load. As locos got heavier, the problem of traction largely solved itself - but steam locos were always notorious for wheel slip.
Unfortunately the Steam Horse blew up, killing thirteen spectators, so we never got to see the spectacle of mechanical horses galloping along the tracks.
Well, there’s always the cog railway, as we still have on Mt. Washington and Pike’s Peak. Or the Funicular railway and Cable Cars More expensive and complex solutions, but they don’t slip.
And much more obvious and simpler mechanical construction
I recall from my undergraduate years participating in an “engineering challenge” contest where the object was to use a restricted bunch of materials that used rubber band power to propel a device across at least ten feet of 1/4" diameter stretched-tight cable. Various devices were built and tested. It wasn’t just distance – the devices were pitted head to head against each other on a 20 foot-long cable. As is generally the case in such competitions, the winning designs were the most simple and elegant. The winners were basically slingshots that propelled themselves in one big burst of speed down the wire “track”.
One guy had designed an incredibly elegant device that used a complex articulated arm to reach forward, grab a piece of the cable, and pull itself along in a series of “steps”, all powered by rubber bands. It didn’t even compete. Not only was it far too slow, but if it had met on of those hurtling slingshots coming down the track at full speed it would’ve been shattered into a hundred pieces.
That’s kind of the way I see Brunton’s locomotive, or Dederick’s Steam Man, or Jansens’a linkage or any of those complex imitations of animal movement – complex, tending to fail at any of a hundred points, and likely to be blown away by a more direct competing principle.
Wrong mechanical elephant,but I really enjoyed the Indian one in Eric Brown’s steampunk novel Jani and the Greater Game
When I was in grad school, there was a pumpkin-chucking competition on campus. The only serious entries were, unsurprisingly, by the mechanical engineering department and the physics department. Ours (the physicists’) design was far more efficient and elegant… but the engineers’ was, while not quite as efficient, large enough that it could have used our entire machine as a counterweight.