How the Concrete Diplodocus paper came to be
February 23, 2023
Last time, I told you about my new paper, The Concrete Diplodocus of Vernal (Taylor et al. 2023), and finished up by saying this: “But Mike, you ask — how did you, a scientist, find yourself writing a history paper? It’s a good question, and one with a complicated answer. Tune in next time to find out!”
Paper 1
The truth is, I never set out to write a history paper. My goal was very different: to belatedly write up my and Matt’s 2016 SVPCA presentation, How Big Did Barosaurus Get? (Taylor and Wedel 2016). In that talk, we discussed a half-prepared jacket at BYU that contains three Barosaurus cervicals which are significantly larger than those of the well-known specimen AMNH 6341. And we went on to note that the giant “Supersaurus” cervical BYU 9024 is morphologically indistinguishable from those of Barosaurus, even though it’s going on for twice the size.
That paper (codename: superbaro) is in progress, and I would estimate it’s about 40% done. But in that paper, I needed to write a brief section in the introduction about AMNH 6341, the keystone specimen for Barosaurus, from which all our perceptions of that animal derive. And it turned out that in that section I had a lot to say, to the point where …
Paper 2
It became apparent that this section needed to be pulled out and become its own paper on the AMNH Barosaurus. As I worked on this, trying to get to the bottom of the complicated history of the mounted cast in the museum’s atrium, I got a lot of help from Peter May of Research Casting International, and from AMNH alumni Lowell Dingus and Gene Gaffney, to the point where they have all been added as authors to the ongoing manuscript.
That paper (codename: baromount) is in progress, and I would estimate it’s about 80-90% done. But in that paper, I needed to write a section on the sources of the various elements that make up the cast — they are not all from AMNH 6341, which is pretty complete as sauropods go but still has a lot of gaps. It turned out, after some poking about, that significant parts of the skeleton were Diplodocus casts, and that they had been made from molds taken from a concrete cast in Vernal, Utah. I started to write up the background information on this, but quickly realised that there was a lot to say, and that it needed to be extracted out into its own paper.
Paper 3

Taylor et al (2023:figure 4). Assembly of the outdoor concrete Diplodocus at the Utah Field House in 1957. (A) In right posterolateral view. The sacrum and fused ilia having been mounted on the main support to begin the process, the hind limbs, last four dorsal vertebrae and first caudal vertebra have now been added. (B) In left anterodorsolateral view, probably taken from the roof of the museum. The mount is almost complete, with only the forelimbs, their girdles and the dorsal ribs yet to be attached. Note that, contra Untermann (1959, p. 367–368), the skull is already in place. Both images scanned by Aric Hansen for the J. Willard Marriott Digital Library, image IDs 1090660 and 1090647. Used by permission, Uintah County Library Regional History Center.
That paper, of course, became The Concrete Diplodocus of Vernal. As I was working on it, I found myself constantly consulting park manager Steve Sroka, and quickly realised that the manuscript had reached the stage of being co-authored. Later in the process, significant contributions from Ken Carpenter went beyond the point of pers. comms, and he was added as a third author. (This paper also received a lot of help from other people, and the acknowledgements are correspondingly extensive and effusive.)
So that is the origin story of yesterday’s paper. But there is another chapter in this story …
Paper 4
As I was writing the section of this paper about the original Carnegie Diplodocus, and in particular about the composition of the mounted skeleton from which the original molds were (mostly) made, it became apparent that this, too, was a long and complicated story. And even though that story has been told in detail multiple times (most notably by Nieuwland 2019), there was still plenty to be told. So this section needed to be pulled out of the CDoV paper (where only a brief summary remains) and become its own paper.
That paper (codename: carnegie) is in progress, and I would estimate it’s about 90-95% done. It, too, has acquired co-authors, including Ilja Nieuwland himself and three Carnegie staff members, but cannot be completed yet as I await an important contribution from an indisposed co-author. Still, it should not be too long before that one is submitted — to be followed by baromount, and then finally superbaro.
So what’s happened here is that a perfectly innocent morphological description paper, based on a conference abstract and a 15-minute talk, has mutated into four substantial papers (of which, admittedly, only one is published so far).
The moral of this story
One moral is that I evidently have very little idea what I am going to work on at any given point in my career. As I was putting together the sidebar page on the Concrete Diplodocus paper, I stumbled across another sidebar page titled Mike’s open projects, which I made in 2020. It lists eight projects that I was going to work on. Of those, one (What do we mean by “cranial” and “caudal” on a vertebra?, Taylor and Wedel 2022) is complete; one (the superbaro project) has advanced but been interrupted by its three offspring papers; and the other six have pretty much not advanced at all (though I do still plan to do them all). Meanwhile, I have done a ton of work on projects that weren’t even on my radar back then, including pneumatic variation (Taylor and Wedel 2021) and finally putting a stake through the heart of neck incompleteness (Taylor 2022).
That’s the bad moral. But there is also a good moral. This is a nice example of what Matt wrote about way back in 2011, for Tutorial 12: How to find problems to work on. Once you actually get started working on something — anything — it will tend to sprout buds. And those buds can easily — too easily, sometimes — become new projects of their own. There is no such thing as a linear programme of research, at least not in my experience. Just an endlessly ramifying tree of fascinating areas that beg to be worked on.
References
- Nieuwland, Ilja. 2019. American dinosaur abroad: a cultural history of Carnegie’s plaster Diplodocus. University of Pittsburgh Press. ISBN: 978-0822945574. doi:10.2307/j.ctvh4zh5n
- Taylor, Michael P., and Mathew J. Wedel. 2016. How big did Barosaurus get?. p. 30 in Anonymous (ed.), SVPCA and SPPC 2016 Liverpool Abstract Book. 49 pp.
- Taylor, Michael P., and Wedel, Mathew J. 2022. What do we mean by the directions “cranial” and “caudal” on a vertebra? Journal of Paleontological Techniques 25:1-24.
- Taylor, Michael P., Steven D. Sroka and Kenneth Carpenter. 2023. The Concrete Diplodocus of Vernal — a Cultural Icon of Utah. Geology of the Intermountain West 10:65-91. doi:10.31711/giw.v10.pp65-91
… and I’m guessing that if you read this blog, you like at least one of these things.
Today sees the publication of a paper that I’m particularly pleased with, partly because it’s so far outside my usual area: The Concrete Diplodocus of Vernal — a Cultural Icon of Utah (Taylor et al. 2023). Let’s jump in by taking a look at the eponymous concrete Diplodocus:

Taylor et al. (2023:figure 5). The completed outdoor Diplodocus mount in a rare color photograph. Undated (but between 1957 and 1989). Scanned by Eileen Carr for the J. Willard Marriot Digital Library, image ID 415530. Used by permission, Uintah County Library Regional History Center.
(On of the things I love about this photo is that it has the same 1950s energy as the Carnegie Tyrannosaurus mount that I posted a while back.)
This paper tells the neglected story of how the Utah Field House museum in Vernal acquired the original Carnegie Diplodocus molds in 1957, after they had languished, unloved and overlooked, in their Pittsburgh basement for forty years; how they were used to cast a Diplodocus from actual concrete (one part cement to three parts aragonite, for those who care); how the molds then went on a series of adventures, never actually yielding another complete skeleton, before being lost or destroyed; how the concrete cast stood for 30 years before the harsh Utah weather degraded it past the point of safety; how it was then used to make a fresh set of molds, and replaced by a new lightweight cast taken from those molds; and how the molds were then used to create a new generation of Diplodocus casts.
It’s a long and fascinating story with lots of twists and turns that I necessarily omitted from that summary — which is why it runs to 27 pages in the lavishly illustrated PDF. I urge you to go and read it for yourself: we wrote it to be an engaging story, and I hope it’s a pretty easy read. (My wife found it interesting, and she once literally fell asleep while I was running a talk to solicit her feedback, so that’s really something.)

Taylor et al. (2023:figure 3). Field House Museum director G. Ernest Untermann (left), and his wife, Staff Scientist Billie Untermann (right), grouting the cast dorsal vertebrae of the Field House’s concrete Diplodocus. 24 January 1957. Scanned by Aric Hansen for the J. Willard Marriot Digital Library, image ID 1086940. Used by permission, Uintah County Library Regional History Center.
This paper was submitted on 2 November 2022, so it’s taken less than five months to go through peer review, editorial processes, typesetting with four(!) rounds of page proofs and online publication. This of course is how it should always be — it’s a bit stupid that I am drawing attention to this schedule like it’s something extraordinary, but the truth is that it is extraordinary. At any rate that makes it fifteen times faster than my long-delayed (mostly my fault) paper on neck incompleteness (Taylor 2022).
I got so deeply into this paper when I was lead-authoring it that the phrase “the Concrete Diplodocus of Vernal” really started to echo around in my head. That is why the paper ends by expressing this wish:
Our dearest hope for this paper is that it inspires someone to create a Dungeons and Dragons module in which the Concrete Diplodocus of Vernal is a quest artifact with magical powers.
But Mike, you ask — how did you, a scientist, find yourself writing a history paper? It’s a good question, and one with a complicated answer. Tune in next time to find out!
References
- Taylor, Michael P., Steven D. Sroka and Kenneth Carpenter. 2023. The Concrete Diplodocus of Vernal — a Cultural Icon of Utah. Geology of the Intermountain West 10:65-91. doi:10.31711/giw.v10.pp65-91
- Taylor, Michael P. 2022. Almost all known sauropod necks are incomplete and distorted. PeerJ 10:e12810. doi:10.7717/peerj.12810
Who is who in this 1903 Carnegie Museum photo?
November 8, 2022
In a paper that I’m just finishing up now, we want to include this 1903 photo of Carnegie Museum personnel:
A few weeks ago I asked for help on Twitter in identifying the people shown here, and I got a lot of useful contributions.
But since then I have seen the Carnegie photo library catalogue for this image (it’s #1010), and it gives names as follows:
- Far left, mostly cropped from image: field worker William H. Utterback
- Seated, facing right: field worked Olof A. Peterson
- Standing at back: preparator Louis Coggeshall (Arthur’s brother)
- Seated, looking to camera: preparator Charles W. Gilmore
- Seated at far table: field worker Earl Douglass
- Standing behind far table: chief preparator Arthur S. Coggeshall
- Sitting at far table, facing left: preparator Asher W. VanKirk
- Seated: illustrator Sydney Prentice
- Sitting on bench: John Bell Hatcher, whose description of Diplodocus carnegii had been published two years previously
Those of you who know a bit of history, do these identifications seem good? Some of the suggestions I got align well with these, but others do not. For example, a lot of people thought that the person here identified as Louis Coggeshall was his better-known brother Arthur.
I’d appreciate any confirmation or contradiction.
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!”
References
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/