I am co-authoring a manuscript that, among other things, tries to trace the history of the molds made by the Carnegie Museum in the early 1900s, from which they cast numerous replica skeletons of the Diplodocus carnegii mount (CM 84, CM 94, CM 307 and other contributing specimens). This turns out to be quite a mystery, and I have become fascinated by it.

Below is the relevant section of the manuscript as it now stands. Can anyone out there shed any further light on the mystery?

So far as we have been able to determine, the casting of the concrete Diplodocus of Vernal was probably the last time the Carnegie Museum’s original molds were used. However, that was not Untermann’s intention. In his 1959 account, he wrote (p368–369):

Several museums in the United States and from lands as distant as Japan and Italy have expressed a desire to acquire the molds and cast a Diplodocus of their own from either plaster or some of the newer synthetics. To date no museum has apparently been able to make satisfactory arrangement for the acquisition of the molds and the casting of a skeleton. We still have the molds in Vernal, and any museum, anywhere, is welcome to them just for hauling them off. […] The Diplodocus on the lawn of the Utah Field House is the eleventh replica to be cast from the molds […] Does anyone wish to cast the twelfth?

From here, though, the story becomes contradictory. Sassaman (1988) reported that “the molds finally fell apart because of old age soon after it [the concrete Diplodocus] was made”. Similarly, Ilja Niewland (pers. comm., 2022) said that “The original moulds were thrown away somewhere during the 1960s (nobody at the [Carnegie Museum] could be more specific than that)”, suggesting that the molds may have been returned to their origin.

Both these accounts seem to be in error, as shown by a 1960 report in the Vernal Express newspaper (Anonymous 1960a; Figure H; see also Carr and Hansen 2005). This says that in the middle of July 1960, the molds were collected by the Rocky Mount Children’s Museum (now the Rocky Mount Imperial Center, Children’s Museum & Science Centre) in North Carolina, with the intention that they would be used to create a twelfth cast which would be mounted outside the museum building next to the Tar River in Rocky Mount’s Sunset Park. But was such a cast ever created? A sequence of reports in the Rocky Mount Evening Telegram from April to July 1960 (Williams 1960, Bell 1960a, Bell 1960b, Anonymous 1960b) enthusiastically announce and discuss the impeding arrival, and the later articles say that museum board president Harold Minges has left for Utah to collect to molds — but then the newspaper goes silent on the subject, and the project is never mentioned again. There is no positive evidence that the molds even arrived in Rocky Mount, far less that they were used to create a new mount. Thus newspaper reports from both Utah and North Carolina say that the molds set out on their journey from one to the other, but neither confirms that they ever arrived. On the other hand, there is also no report of the molds being lost or destroyed, so perhaps the most likely interpretation is that they arrived in Rocky Mount, but were found to be in worse condition than expected and quietly left in storage. This interpretation is supported by Rea (2001:210) who reported that “from Vernal the molds kept travelling — first, to the Rocky Mount Children’s Museum in Rocky Mount, North Carolina, although a cast was never made there”. Similarly, Moore (2014:234-235) stated that “From Vernal, Utah, [CM] molds of Diplodocus carnegii are shipped to Rocky Mount Children’s Museum in Rocky Mount, North Carolina. Because of the age-related damage to the molds, a cast was never prepared”.

Hurricane Floyd devastated Rocky Mount in 1999, with flooding from the River Tar destroying the original Children’s Museum along with all its exhibits and records (Leigh White, pers. comm., 2022), so no records survive that could confirm the molds’ arrival or any subsequent use. The museum was located next door to a municipal water treatment facility that also flooded and released unknown chemicals, so museum property that might have otherwise been salvageable in that area was deemed contaminated and required to be destroyed. If the molds were in storage at the Children’s Museum at this time, then this was likely the end of their story.

The Children’s Museum was re-established at the newly built Imperial Centre, where it still resides, but no trace exists there of molds or casts of Diplodocus. Corroborating the hypothesis that no cast ever existed, most staff who worked at the museum in the 1980s do not recall any such cast (Leigh White, pers. comm., 2022). Contradicting this, however, Jan Engle Hicks, Curator of Education at the Rocky Mount Children’s Museum from 1971–2002, has a memory of Diplodocus casts being on exhibit at the museum when she started work in 1971. She does not recall if they were still part of the museum collection in 1999 when the collection was destroyed.

Whether or not a cast was made at Rocky Mount, it is possible that this was not the end for the molds. Rea (2001:210) continues: “Eventually the molds found their way to the Houston Museum of Science, where they were used to fill in gaps in the Diplodocus hayi skeleton that had been swapped from Pittsburgh to Cleveland before ending up in Houston”, citing a personal communication from John S. McIntosh. (The skeleton in question is that of CM 662, which became CMNH 10670 in Cleveland, then HMNS 175 in Houston. Having been nominated as the holotype of the new species Diplodocus hayi by Holland (1924:399), the species was later moved to its own new genus Galeamopus by Tschopp et al. (2015:267).)

Due to the loss of the Rocky Mount Children’s Museum records, we cannot tell whether they ever shipped the molds to Houston; and we have not been able to obtain information from the Houston Museum. Brian Curtice (pers. comm., 2022) reports that he was in Houston in 1995 and did not see the molds in the collection, nor hear of their ever having been there. In the absence of evidence that the molds ever made it to Houston, it seems at least equally likely that the missing bones in HMNS 175 were cast and supplied by Dinolab, using the second-generation molds described blow, and that Rea (2001) misreported this.

As recently as 1988, Rolfe (1988) wrote on behalf of the Royal Museum of Scotland, “At present I am exploring the possibility of re-using the Carnegie Museum, Pittsburgh moulds, although there is considerable doubt about whether they are up to the job, after so much previous use”. Sadly, his letter does not mention their then-current whereabouts.

In an unpublished manuscript, Madsen (1990:4) wrote that “The fate of the initial set of molds is somewhat in question, but Wann Langston (personal communication, 1989) suggests that they seem to have been lost, strayed, or stolen during transport from ? to ?. Principles contacted in regards to the disposition of the molds could not provide specific information.”. Infuriatingly, the question marks are in the original. Since both Langston and Madsen are now deceased, there is no way to discover on which of the molds’ journeys Langston thought they were lost or destroyed. It is unlikely, at least, that Langston had in mind the their initial journey from Vernal to Rocky Mount. Kirby (1998:4) wrote that “Somewhere along the line, as the story goes, the molds received from the Carnegie had been shipped to a school down south and never arrived. So they were lost”. Since Rocky mount is about 2000 miles east (not south) of Vernal, “a school down south” could not have referred, in a Utah publication, to a museum out east. The Houston museum also does not seems an especially likely candidate for this designation, being 1300 miles southeast of Vernal.

Putting it all together, there is no way that all the reports cited here can be accurate. Perhaps the most likely scenario is this: the molds were successfully shipped to Rocky Mount in July 1960 (Anonymous 1960a, Anonymous 1960b) but found to be unusable (Rea 2001:210, Moore 2014:234-235) and left in storage. At some later point there were shipped to a school in a southern state (Kirby 1998:4) but did not arrive (Langston cited in Madsen 1990:4). This may have happened in late 1988 or early 1989, between Rolfe’s (1988) letter that expressed an interest in using the molds and Langston’s personal communication to Madsen in 1989. Where the molds are now, and why they did not arrive, we can only speculate. As Madsen (1990:4) concluded, “It is truly a mystery that an estimated 3–6 tons of plaster molds could simply vanish!”


Anonymous. 1960a. Dinosaur molds take long ride to No. Carolina children’s home. Vernal Express, 14 July 1960, page 15. https://newspapers.lib.utah.edu/ark:/87278/s6zk6w6s/21338221

Anonymous. 1960b. Something ‘big’ for a fact. Rocky Mount Evening Telegram, 8 July 1960, page 4A. https://newspaperarchive.com/rocky-mount-evening-telegram-jul-08-1960-p-4/

Bell, Mae. 1960a. Dinosaur’s coming here brings questions galore. Rocky Mount Evening Telegram, 14 May 1960, page 2. https://newspaperarchive.com/rocky-mount-evening-telegram-may-14-1960-p-2/

Bell, Mae. 1960b. ‘Dinosaur’ soon to arrive here. Rocky Mount Evening Telegram, 3 July 1960, page 3A. https://newspaperarchive.com/rocky-mount-evening-telegram-jul-08-1960-p-8/

Carr, Elaine, and Aric Hansen. 2005. William Randolf Turnage, Dee Hall, and Ernest Untermann [archive photograph with metadata]. University of Utah, J. Willard Marriott Digital Library, image 1086142. https://collections.lib.utah.edu/details?id=1086142

Holland, William J. 1924. The skull of Diplodocus. Memoirs of the Carnegie Museum 9(3):379–403.

Kirby, Robert. 1998. Danny and the dinosaurs. Chamber Spirit (newsletter of the Vernal area Chamber of Commerce) 3(4):1–6.

Madsen, James H. 1990. Diplodocus carnegiei: Production and design of replica skeletons. Unpublished draft manuscript. (No author is named in the manuscript, but Madsen’s son Chris believes it is his work.)

Moore, Randy. 2014. Dinosaurs by the Decades: A Chronology of the Dinosaur in Science and Popular Culture. Greenwood, Westport, Connecticut.

Rea, Tom. 2001. Bone Wars: The Excavation and Celebrity of Andrew Carnegie’s Dinosaur. University of Pittsburgh Press, Pittsburgh, PA.

Rolfe, William D. I. 1988. Untitled letter to LuRae Caldwell (Utah Field House). 24 October 1988.

Sassaman, Richard. 1988. Carnegie had a dinosaur too. American Heritage 39(2):72–73.

Tschopp, Emanuel, Octávio Mateus and Roger B. J. Benson. 2015. A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda). PeerJ 2:e857. doi:10.7717/peerj.857

Untermann, G. Ernest. 1959. A replica of Diplodocus. Curator 2(4):364–369. doi:10.1111/j.2151-6952.1959.tb00520.x

Williams, Oliver. Pre-historic dinosaur to tower over city; giant animal four times taller than man. Rocky Mount Evening Telegram, 24 April 1960, page 3B. https://newspaperarchive.com/rocky-mount-evening-telegram-apr-24-1960-p-11/

I’ve been in contact recently with Matt Lamanna, Associate Curator in the Section of Vertebrate Paleontology at the Carnegie Museum of Natural History — which is obviously the best job in the world. Among a batch of photos that he sent me recently, I seized on this gem:

Tyrannosaurus rex, Diplodocus carnegii, Apatosaurus louisae and multiple mostly juvenile individuals of Homo sapiens. Photograph taken between 1941 and 1965. Courtesy of Carnegie Museum of Natural History.

There’s so much to appreciate in this picture: the hunchbacked, tail-dragging Tyrannosaurus; the camarasaur-style skull on the Apatosaurus; the hard-to-pin-down archaic air of Diplodocus.

But the thing I love about it is the 1950s kids. (Or, to be fair, maybe the 1940s kids or early 1960s kids, but you get the point.) They way they’ve all been asked to look up at the tyrannosaur skull, and are obediently doing it. How earnest they all appear. How they’re all dressed as tiny adults. How self-consciously some of them have posed themselves — the thoughtful kid one in from the left, his foot up on the plinth and his chin resting on his hand; the cool kid to his right, arms crossed, interested but careful not to seem too impressed.

Where are these kids now? Assuming it was taken in 1953, the midpoint of the possible range, and assuming they’re about 12 years old in this photo, they were born around 1941, which would make them 81 now. Statistically, somewhere around half of them are still alive. I wonder how many of them remember this day, and the strange blend of awe, fascination, and self-consciousness.

This is a time-capsule, friends. Enjoy it.

We’ve shown you the Apatosaurus louisae holotype mounted skeleton CM 3018 several times: shot from the hip, posing with another massive vertebrate, photographed from above, and more. Today we bring you a world first: Apatosaurus from below. Scroll and enjoy!

Obviously there’s a lot of perspective distortion here. You have to imagine yourself lying underneath the skeleton and looking up — as I was, when I took the short video that was converted into this image.

Many thanks to special-effects wizard Jarrod Davis for stitching the video into the glorious image you see here.

The most obvious effect of the perspective distortion is that the neck and tail both look tiny: we are effectively looking along them, the neck in posteroventral view and the tail in anteroventral. The ribs are also flared in this perspective, making Apato look even broader than it is in real life. Which is pretty broad. One odd effect of this is that this makes the scapulae look as though they are sitting on top of the ribcage rather than appressed to its sides.


Yes, we’ve touched on a similar subject in a previous tutorial, but today I want to make a really important point about writing anything of substance, whether it’s a scientific paper, a novel or the manual for a piece of software. It’s this: you have to actually do the work. And the way you do that is by first doing a bit of the work, then doing a bit more, and iterating until it’s all done. This is the only way to complete a project.

Yes, this is very basic advice. Yes, it’s almost tautological. But I think it needs saying because it’s a lesson that we seem to be hardwired to avoid learning. This, I assume, is why so many wise sayings have been coined on the subject. Everyone has heard that “A journey of a thousand miles begins with a single step”, attributed to Lao Tzu in maybe the 5th Century BC. More pithily, I recently discovered that Williams Wordsworth is supposed to have said:

To begin, begin.

I love that. In just three words, it makes the point that there is no secret to be learned here, no special thing that you can do to make beginning easier. You just have to do it. Fire up your favourite word processor. Create a new document. Start typing.

And to Wordsworth’s injunction, I would add this:

To continue, continue

Because, again, there is no secret. You just have to do it.

Mounted skeleton of Diplodocus carnegii holotype CM 84 in the rare dorsal view.

At the moment I am working on four separate but related papers. Honestly, sometimes it’s hard even keeping them straight in my head. Sometimes I forget which one I am editing. It would be easy to get overwhelmed and … just not finish. I don’t mean it would be easy to give up: that would be a decision, and I don’t think I would do that. But if I listened to my inner sluggard, I would just keep on not making progress until the matter become moot.

So here is what I do instead:

  • I pick one of the papers, which is the one I’m going to work on that evening, and I try not to think too much about the others.
  • I figure out what needs to be in that paper, in what order.
  • I write the headings into a document, and I put an empty paragraph below each, which just says “XXX”. That’s the marker I use to mean “work needed here”.
  • I use my word-processor’s document-structuring facilities to set the style of each of the headings accordingly — 1st, 2nd or occasionally 3rd level.
  • I auto-generate a table of contents so I can see if it all makes sense. If it doesn’t, I move my headings around and regenerate the table of contents, and I keep doing that until it does make sense.
  • I now have a manuscript that is 100% complete except in the tiny detail that it has no content. This is a big step! Now all I have to do is write the content, and I’ll be finished.
  • I write the content, one section at a time. I search for “XXX” to find an unwritten section, and I write it.
  • When all the “XXX” markers have been replaced by text, the paper is done — or, at least, ready to be submitted.


First, that list makes it sound like I am really good at this. I’m not. I suck. I get distracted. For example, I am writing this blog-post as a distraction from writing a section of the paper I’m currently working on. I check what’s new on Tweetdeck. I read an article or two. I go and make myself a cup of tea. I play a bit of guitar. But then I go back and write a bit more. I could be a lot more efficient. But the thing is, if you keep writing a bit more over and over again, in the end you finish.

Second, the path is rarely linear. Often I’m not able to complete the section I want to work on because I am waiting on someone else to get back to me about some technical point, or I need to find relevant literature, or I realise I’m going to need to make a big digression. That’s fine. I just leave an “XXX” at each point that I know I’m going to have to revisit. Then when the email comes in, or I find the paper, or I figure out how to handle the digression, I return to the “XXX” and fix it up.

Third, sometimes writing a section blows up into something bigger. That’s OK. Just make a decision. That’s how I ended up working on these four papers at the moment. I started with one, but a section of it kept growing and I realised it really wanted to be its own paper — so I cut it out of the first one and made it its own project. But then a section of that one grew into a third paper, and then a section of that one grew into a fourth. Not a problem. Sometimes, that’s the best way to generate new ideas for what to work on: just see what come spiralling out of what you’re already working on.

None of these caveats change the basic observation here, which is simply this: in order to get a piece of work completed, you first have to start, and then have to carry on until it’s done.


Here at SV-POW! Towers, we like to show you iconic mounted skeletons from unusual perspectives. Here’s one:

Apatosaurus louisae holotype CM 3018, mounted skeleton in the public gallery of the Carnegie Museum of Natural History: head, neck, torso and hip in right posterolateral view. Photograph by Matt Wedel, 12th March 2019 (my birthday!)

Oh, man, I love that museum. And I love that specimen. And I love the one that’s standing next to it (Diplodocus CM 82, natch.) I’ve got to find a way to get myself back out there.

That’s all: just enjoy.

Last Thursday I gave a public lecture for the No Man’s Land Historical Society in the Oklahoma Panhandle, titled “Oklahoma’s Jurassic Giants: the Dinosaurs of Black Mesa”. It’s now on YouTube, on the No Man’s Land Museum’s channel.

There’s a point I want to make here, that I also made in the talk: we can’t predict the value of natural history collections. The first sauropod vertebrae that Rich Cifelli and Kent Sanders and I CT scanned back in the spring of 1998 belonged to what would become Sauroposeidon, but most of the ones we scanned after that were Morrison specimens collected by J. Willis Stovall’s crews from the Oklahoma Panhandle between 1934 and 1941. Those scans formed the core of the pneumaticity research that fleshed out the Sauroposeidon papers (Wedel et al. 2000a, b), and was more fully developed in my Master’s thesis and the papers that came out of that (Wedel 2003a, b).

OMNH 1094, a mid-cervical vertebra of Brontosaurus in right lateral view. If you’ve seen one of my talks or my first few papers, you’ve seen this vert. I just realized that I have almost all the photos I need to do a proper multi-view; stand by for a future post on that.

So the foundation of my career was built in large part from collections that had been made 60 years earlier, decades before CT was invented. I’ll also note here that Xenoposeidon — Mike’s fourth paper (Taylor and Naish 2007), but the one which really launched his career as a morphologist — is based on a specimen collected in the 1890s. Natural history collections are not only resources for making comparisons, but also the engines of future discovery, and building and maintaining them is one of the most significant contributions to science that we can make.

I thank a bunch of folks at the end of the talk, but I especially want to thank Brian Engh for the use of his art, and Anne Weil for inviting me to collaborate on the sauropod material from the Homestead Quarry. Looking forward to more adventures!


Remember this classic XKCD comic?

You should talk to the girl down the hall; I think you'd like her. Lemme know if you find out why she's ordering all those colored plastic balls.

Well, this is me over the last couple of weeks:Isn't it weird how looking at those cervicals in either lateral OR dorsal views gives a completely misleading idea of their shape?

I made this for my own amusement, and thought you guys may as well get to benefit from it, too.

Melstrom et al. (2016:figure 4). Pectoral vertebrae of a juvenile specimen of Barosaurus sp. (DINO 2921) from the Upper Jurassic Morrison Formation of Utah, U.S.A., in right lateral view (red-cyan anaglyph made from stereopair).



  • Melstrom, Keegan M., Michael D. D’Emic, Daniel Chure and Jeffrey A. Wilson. 2016. A juvenile sauropod dinosaur from the Late Jurassic of Utah, U.S.A., presents further evidence of an avian style air-sac system. Journal of Vertebrate Paleontology 36(4):e1111898. doi:10.1080/02724634.2016.1111898


For this forthcoming Barosaurus paper, we would like to include an establishing photo of the AMNH Barosaurus mount. There are two strong candidate photos which we’ve used before in an SVPCA talk, but since this is a formal publication we need to be more careful about copyright. Here are the photos, which are the property of their respective rightsholders:

This one is hard to find at all, at least using Google’s reverse image search. Whereas this one …

… is sprinkled all over the Internet, but (in all the cases I’ve seen so far) without attribution.

Does anyone have the necessary skills to track down who the rightsholder is for either of these? Thank you!

Matt and I are writing a paper about Barosaurus cervicals (yes, again). Regular readers will recall that the best Barosaurus cervical material we have ever seen was in a prep lab for Western Paleo Labs. We have some pretty good photos, such as this one:

Barosaurus cervical vertebra lying on its right side in anterodorsal view (i.e. with dorsal to the left), showing the distinctive shape of the prezygapophyseal rami.

The problem is that this specimen was privately owned at the time we saw it, and so far as we know it still is. So according to all standard procedures, we should consider it unavailable to science until such time as it is deposited in an accredited museum. (I was pretty sure the SVP has an explicit policy to this effect, but I couldn’t find it on the site. Can anyone?)

So what should we do? All the possible courses of action seem unfortunate.

1. We could go ahead and include photos, drawings and descriptions of these vertebrae in the paper — but that would violate community norms by building an argument on observations that cannot be in general be replicated by other researchers. (For all we know, these vertebrae are now decorating Nicolas Cage’s pool room.)

2. We could omit these vertebrae from the paper, but use the information we gained from examining them in formulating our diagnostic criteria for Barosaurus cervicals — but this would also not really be replicable, plus it would have that horrible “we know something that you don’t” quality.

3. We could act as though these vertebrae do not exist, or as though we had never seen them, writing the paper based only on our observations of inferior material and of the good AMNH 6341 that is not accessible for study or photography — but that would make our characterisation of Barosaurus cervical morphology less helpful than it could be.

4. We could refrain from publishing on Barosaurus cervicals at all until such time as these vertebrae, or similarly well-preserved ones, are available to study at accredited institutions — but that would simply deprive the world of an interesting and exciting study.

Is there a fifth path that we have not seen? And if not, which of these four is the least objectionable?