Author Interview--Scott Hippensteel (Sand, Science, and the Civil War) Part 1

Hello H-CivWar Readers:

Today we feature Scott Hippensteel to talk about his new book, Sand, Science, and the Civil War: Sedimentary Geology and Combat, published by University of Georgia Press in March 2023.

Scott Hippensteel is associate professor of earth sciences at the University of North Carolina at Charlotte. He received his Ph.D. in Geology from the University of Delaware. He is the author of Rocks and Rifles: The Influence of Geology on Combat and Tactics during the American Civil War (2019) and Myths of the Civil War: The Fact, Fiction, and Science behind the Civil War’s Most-Told Stories (2021).

Scott, you are a Geologist, interested in, and I looked this up on your faculty page, Environmental Micropaleontology, Geoarchaeology, and Coastal Geology, how did you write a book, actually this is your third one, on the Civil War?

SH: When I was an undergrad in college I told my dad, a mathematics professor, that I was switching my major from geosciences to history.  He convinced me that I would have a much easier path to a successful college teaching career if I stayed in the sciences and I took his advice.  History has always fascinated me and if you look at the areas of research interest that you pulled from my faculty page, they all have one thing in common:  they are historical sciences.  Paleontology is the history of life on the planet.  Geoarchaeology involves using the tools of the geosciences to study humans of the past.  Even coastal geology spends a great deal of time studying how coastlines and the coastal plain have evolved over time.  

My love of history and the interaction between history and science was fostered at an early age.  I grew up a short drive from the Gettysburg battlefield and spent countless hours as a teenage hiking around the battlefield and studying the fascinating terrain.  There is no better place on the planet to see the interaction between geology and military history than the square mile that includes Devil’s Den and Little Round Top.  Later, when I was in graduate school, I spent even more time in the marshes of the southeast searching for ancient hurricane deposits as part of my dissertation research.  This inevitably led me to the most stable and long-lasting portions of the shoreline, which also happened to be the safest location in the 19th Century to build defensive fortifications like Fort Fisher, Battery Wagner, Fort Macon, and Fort Pulaski.  This led the curious scientist/historian in me to ask all kinds of questions:  Why did Fort Macon and Pulaski surrender so quickly, without much of a real fight, while Fisher and Wagner proved almost impossible to capture for the Federal army and navy?  The answer seemed obvious – brick vs. sand, yet no history books discussed this.

The real motivation for the book occurred when I brought my wife and daughter on a “family” vacation to yet another battlefield.  This time it was Stones River and we happened to be visiting on the 155th anniversary of the battle.  This was the first time ever that the National Park Service allowed reenactors onto the actual battleground and we witnessed soldiers pretending to fight and take cover in the natural limestone trenches (karrens) at the center of the Union line.  I was struck by just how much of a force-multiplier the sedimentary rocks would have been for the federal infantry and I quickly made connections to numerous other examples of “soft rock” battlefields from across the Coastal Plain and Mississippi River Valley.  

What do you argue in Sand, Science, and the Civil War?

SH: Sedimentary geology, and specifically sand, played a much larger role in the strategy, tactics, and combat of the Civil War than has been appreciated by historians.  Sediments influenced the fighting on all scales.  On the defensive, any type of sediments could be piled to provide soldiers with concealment and cover; during the same fight, sediments might be exploited on the offense, using fragments of rock as weapons. At Second Manassas, for example, when members of the Stonewall Brigade ran low of ammunition, they (fittingly) threw cobbles with concussive results. On other battlefields other grain sizes were used as weapons as well, including boulders rolled down mountains and sand thrown in the eyes of the enemy during close-quarters combat. 

Sediments can also make weapons more deadly or undermine their damaging effects. If an exploding artillery shell hits very coarse sediments, a new rocky shrapnel will result, but if the same shell strikes fine-grained sediment, the exploding heavy ordnance can suddenly be rendered nearly harmless. Fine, penetrating sediment can also make a rifle musket as useful in combat as a nine-pound club.

Perhaps the best example of how sedimentary geology and sand were underappreciated by commanding officers of the Civil War, and later military historians, is found with the education of Union Maj. Gen. Quincy Gillmore.  On July 18, 1863, Gillmore observed as the Union army and navy sent crossfire of nearly ten thousand heavy artillery shells into a sand fortification, Battery Wagner. Confident of the nearly total reduction of the fort and its eighteen-hundred-man garrison, the commanding officer ordered five-thousand of his men to assault and capture the disabled battery. To the great dismay of the Federal infantry and their leadership, however, what appeared to be a battered fort with a wounded garrison was instead a fully functional fortification with a nearly complete defensive capability. The ten-hour bombardment, at times raining shells at two-second intervals, had killed only eight men and wounded only twenty.  Gillmore’s grand assault on Battery Wagner turned disastrous for the Union, who suffered 1,515 casualties during the failed assault (more than 30 percent of the attacking force, including Matthew Broderick and Denzel Washington). The outnumbered Confederate defenders, sheltered in the sand, lost only 222 men.

What is truly surprising about this tragic story, however, is that these sedimentary lessons were not learned by others:  The same tactics would be employed several more times along the shoreline during the last two years of the war, including against the grandest of all the sand fortresses, Fort Fisher.

The sand sections were fascinating. You already mentioned that historians had not put the soils and battles in conversation, we recently had an outpouring of books on various environmental factors, weather, and so on. As you say, some of the soil determinations are right in your face, like the sand of Wagner or Fisher—why has soil been absent so far?

SH: Military history books are almost exclusively written by historians, not scientists.  There are several examples of historians either contributing excellent discussions about the relationship between soils – and occasionally sediments – and military history or collaborating with natural scientists to produce environmentally-themed history books.   However, most of the existing literature dealing with the relationship between sedimentary geology and the Civil War has focused on soil and agriculture, rather than sediments and combat.  Harold Winters is an exception, having dedicated many pages of his comprehensive work Battling the Elements: Weather and Terrain in the Conduct of War (1998) to the formation and impact of mud on fighting throughout the history of warfare.  More recently, Lisa Brady’s War upon the Land: Military Strategy and the Transformation of Southern Landscapes during the American Civil War (2012) and Brian Allen Drake’s The Blue, the Gray, and the Green: Toward an Environmental History of the Civil War (2015) applied an environmental-history approach to the war and its aftermath. These texts deal indirectly with sedimentary geology, discussing depositional environments and artificial modifications to the landscape that were the direct result of the fighting on and around the battlegrounds.  Part of the reason I was drawn to the University of Georgia press as a potential publisher was these last two books and their interdisciplinary approaches.  

There are other recent books that have started to explore how the geosciences influenced the Civil War in vastly different ways.  For example, Kenneth Noe’s The Howling Storm: Weather, Climate, and the American Civil War (2020) goes into great detail about how the weather and climate impacted the fighting during the Civil War and it is a really excellent and unique contribution.

Related to that question, you are approaching history as a scientist. I admit, there were a few moments where I struggled with the science—how did you balance science and history? Your history readers are in history because science was not their thing—how do you avoid overwhelming your audience but provide just the right amount of scientific detail?

SH: This is why I am so thankful that this is a peer-reviewed book.  Although all of the reviewers for my book are unknown to me, I suspect they were mostly (all?) historians.  I joked in the acknowledgments that the manuscript was subjected to 537 blinded reviews – it was probably only seven – but their critical comments really helped me find a practical path between writing a science and history book.  Early reviews in the process consistently mentioned terminology and concepts that seemed fundamental to me, as a geology professor, but were unclear to the reader.  These critiques, along with discussions with the University of Georgia’s Stephen Berry, helped me to rewrite and reorganize the text to make it more accessible to all audiences.

There is a second value offered by the peer-review process that involves expertise, and specifically, the confidence you are permitted when crafting a book partly outside your own field of professional research.  I wouldn’t have felt as comfortable producing this book without having several brilliant historical minds looking over my shoulder and essentially scrutinizing my presentation and interpretation of the past.

I am glad you received so many helpful comments and it shows in the book's accessibility. Let’s turn to the book, you have lots of science in the book and I would assume most of the officers and especially soldiers did not have a solid background in geology, correct? In how much did officers take soil into consideration for battles, routes, or winter camps and how much was just coincidental or prudent use?

SH: Most of the soldiers and officers didn’t have any basic understanding of geology, in large part because it was a brand new science in the 1860s. I drew a connection between the most influential American military scholar prior to the war, Denis Hart Mahan, and the most important geologist, Charles Lyell.  Both published their first important textbook within a few years of each other in the late 1830s.  As a result, the officers educated prior to the outbreak of fighting would have taken courses in topography and engineering, but with no connection to geology.
The field commander who most likely had the best understanding of sedimentary geology at the beginning of the war was Union general William Rosecrans.  Before the war he spent some time studying minerals and rocks, but today you’d consider him a hobbyist or, at best, an amateur geologist.  I’ve always thought, from a geological perspective, that it was a shame that George “The Rock of Chickamauga” Thomas never got to face off against Stonewall Jackson in a major battle.

As far as the officers’ consideration of soil with respect to battles, routes of travel, or winter camps, the answer is more complicated.  For battles, there is clear evidence that they were more concerned with topography (high ground) than soil thickness.  As a result, many great defensive stands were made on slightly higher ground that was absent of trenches or field fortification.  Some of the best terrain at Gettysburg and Stones River, for example, had the thinnest soil.

With respect to marches and road conditions, I went into some detail discussing what, geologically, makes a road impassable or causes it to deteriorate quickly.  I don’t think the officers and logisticians at the time would have been concerned with whether the clay was cohesive or adhesive, only whether the men could march across it and the wagons could get through.  The result was often a rapid decline of the road conditions and fiascos like Burnsides’ infamous Mud March.

One area where geology influenced tactics that hasn’t been widely discussed also deals with the finest of sedimentary particles.  Add water to clay and silt and you get a muddy mess.  Dry the same material completely, send tens of thousands of men stomping across it, and you get an unbearable dust storm.  Consider how the slightly damp ground kept the dust down for Jackson’s surprise flanking march at Chancellorsville compared with, only a month later, how dust betrayed Longstreet’s march in front of the Union left at Gettysburg.  Interestingly, soldiers’ diaries contain a similar number of (justifiable) complaints about this tiny sediment, regardless of whether it was too wet or completely dry.