Fortification Friday: What is a profile?

I often incorporate accurate terminology to describe the fortifications.  But some of those terms have either fallen into dis-use, carry new meanings today, or simply may not be clear to all readers. And why would an artillery guy be worried about fortifications?  Well I look at it this way – on the battlefield the antithesis of artillery is fortification.  Artillery came into being as a means of destroying fortifications.  Fortifications evolved further as a means to counter the use of advanced artillery.  So we have a yin-yang relation going on with artillery and fortifications.   Anyone seriously considering one must take into account the other (keep that in mind when considering “tactics” books out there today).

Back during the sesquicentennial, I dabbled with the idea of a recurring series focused on this fortification terminology.  But sesqui being sesqui, there was always too many “on this day” stuff to write about and little room for general studies.  That said, the 150ths of the war are over and I am revisiting that premise.  So let me re-launch “Fortification Friday.”

One more point of order before “launching” into this “vocabulistics” study.  Years ago a great site existed which did just what I’m embarking upon.  The web site is dark now, but the “Civil War Field Fortifications Website” held a “Dictionary of Fortification” that provided “A lexicon of significant and arcane terminology applicable to the study of the art and science of fortification as it was practiced during the middle period of the nineteenth century.”  A fabulous resource that got right down to the details.  Sadly, the webmaster (PE McDuffie) stopped updating in about 2007, and the last time the site rendered was in 2010.  While I am not going to resurrect that body of knowledge, I would offer that up, by way of the Internet Archive, for readers to continue exploring this subject.

OK, introduction aside, let me offer up a term I’ve used often before – PROFILE.

McDuffie’s web-dictionary define profile as:

… a cross section of the parapet and ditch taken along a line perpendicular to the general direction of the interior crest of the parapet or from the interior side of the parapet exterior side of the work. It shows, basically, a vertical slice of the work and graphically describes the elevation, thickness and general arrangement of the various elements of the work. Profiles of all major field works included two basic elements: the parapet and the ditch.

From an American-centric point of view that is, Dennis Hart Mahan is “the source” for both theory and practice of fortification.   Mahan also explained profiles in context with the parapet and ditch:

To enable troops to fight with advantage, the intrenchements should shelter them from the enemy’s fire; be an obstacle in themselves to the enemy’s progress; and afford the assailed the means of using their weapons with effect.  To satisfy these essential conditions, the component parts of every intrenchement should consist of a covering mass, or embankment, denominated the parapet, to intercept the enemy’s missiles, to enable the assailed to use their weapons with effect, and to present an obstacle to the enemy’s progress, and of a ditch, which, from its position and proximity to the parapet, subserves the double purpose of increasing the obstacle which the enemy must surmount before reaching the assailed, and of furnishing the earth to form the parapet….

The general form of a parapet and ditch, to fulfil the above conditions, will be best understood by an examination of the profile, which is a section of the intrenchment made, by a vertical plane, perpendicular to the general direction of the intrenchment.

Mahan offered this figure to illustrate a profile showing the “textbook” layout of the parapet and ditch.

Plate1Figure1

This would be the profile of a “classic” fortification. Mahan’s annotation pointed out the parapet defined as points A-B-C-D-E-F.  The ditch was from G-H-I-K.  Beyond that, the glacis was points L-M-N.  There are a dozen other terms called out within this profile – banquette slope, interior slope, superior slope, exterior slope, scarp, and counterscarp, to name a few.  But the basic element was, as Mahan pointed out, the parapet and ditch.

The profile, along with the line of the works, defines the fortification itself and allows the engineer to depict the three dimensional nature of the fortification onto a two dimensional diagram. Engineers had to depict the arrangement of parapet and ditch, in the vertical plane, in order to relate the details of their plan.  You know, the old “measure twice, cut once” rule?  Or in this case, draw it out before you start shoveling. Every fortification, permanent or field, has a profile, even if the elements of the parapet and ditch don’t match up with the “classic” form.  When discussing the photos of Fort Johnson, I cited these profiles drawn by Federal engineers as they surveyed the Confederate works:

Profiles

We really don’t see a “ditch” in these profiles, do we?  Well that’s because the “ditch” of Fort Johnson was for all practical purposes the waters of Charleston Harbor.  And I argue that Fort Johnson’s ditch served the purpose very well from April 1861 to February 1865.   We also see a lot of details within the parapet beyond just slopes and scarps.  Earthworks were not just simple forms.  Each was tailored, by the plan, to fit the situation.  Each plan factored the needs and resources on hand.  In that light, consider the “profile” as a component of the language in which the engineer related the plan.

(Citations from Dennis Hart Mahan, A Treatise on Field Fortifications, New York: John Wiley, 1852, pages 1-2; And Civil War Field Fortifications Website, linked above.)

5 thoughts on “Fortification Friday: What is a profile?

  1. Craig, I’ll have to admit that a quick misread of this post’s title, “Fortification Friday,” caused me to question why you were now “dabbling” into a non-Civil War topic, but heck, as long as my eyes were now sharply focused on the post, why not go ahead and read it? And now that I have carefully reviewed this post (twice), I am utterly convinced all you gunners retain mathematical talents we others do not possess. In other words, once you got deep into the “classic form,” I didn’t understand more than a couple of phrases, if that.

    Now, back to cavalry..

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