Gettysburg, Day 2: The Services Demanded of a Reconnoitring Officer

In my interpretation, the second day of the battle of Gettysburg should be divided into two parts. Most written works and tours will focus on the second of those parts – the actual fighting from the late afternoon into the evening. I will not say that focus is misplaced, as the “event” of the battle itself turned within those precious hours. Stories of valor, alongside those of failure, intermingle with poignant, touching, and very human recollections from those moments. Indeed, if one wishes to study the fighting, that’s where it was at!

Working back, we can consider all the activities prior to the attack on the south end of the battlefield – moment when Law and Robertson’s brigades step forward at the lead of Hood’s Division – as the “run-up” to the fighting. To me, this is the “staff battle” phase of the day. Sure, the troops did the marching, maneuvering, and, in some areas of the field, skirmishing. But it was the staffs, on both sides of the line, which facilitated the preparation … or lack thereof … or improper preparations… for the actions that followed in the afternoon. Chief among those preparatory staffing activities was reconnaissance.

The most important reconnaissance conducted on July 2, 1863 from the Confederate side is that conducted around daybreak by several of Lee’s staff (augmented… or at least concurrent with some of Longstreet’s staff). Brigadier-General William Pendleton, Colonel Armistead Long, and Captain Samuel Johnson are the notables involved (again from Lee’s staff, with others from Longstreet’s staff joining… not to downplay that, but my intent is not to get too far down into the details here). It is Johnston, being the engineer, who provided the most information from this effort. And receives the most attention. Likewise on the Federal side, there were several staff officers conducting reconnaissances throughout the morning hours. Indeed, one has to wonder how the staffs of blue and grey managed to miss one another!

We spoke of intelligence gathering yesterday. And indeed, reconnaissance one method employed to harvest the wheat, under the analogy offered in that post. With that in mind, let us ponder this follow up question today:

Just what is a military reconnaissance?

Well let us consult with the professor of West Point, the esteemed Dennis H. Mahan, as we always should on such matters:

There are no more important duties, which an officer may be called upon to perform, than those of collecting and arranging the information upon which either the general, or daily operations of a campaign must be based.  For the proper performance of the former, acquirements of a very high order, in the departments of geography and statistics, are indispensable requisites; to which must be added a minute acquaintance with topography, and a good coup d’œil militaire for that of the latter.

However detailed and perfect may be a map, it can never convey all the information that will enable an officer to plan, even an ordinary march, with safety; still less, operations that necessarily depend, for their success, upon a far greater number of contingencies.  To supply these deficiencies of maps, an examination of the ground must be made by the eye; and verbal information be gained, on all the points connected with the operation over this ground.  This examination and collection of facts is termed a Reconnaissance.

Outpost, Mahan, page 105.

Unpacking Mahan, because that’s what I do…. we see the professor put great emphasis on the duties and obligations of the officer conducting the reconnaissance. After all, as we alluded to yesterday, much of the commander’s understanding of the situation, that picture in his mind – n So that officer must be a person of ability in particular fields of knowledge. Below this passage, Mahan insisted the officer be “cool-headed and truthful; one who sees things as they are, and tells clearly and precisely what he has seen.”

And what is this coup d’œil militaire? Ah… from Napoleon himself… “There is a gift of being able to see at a glance the possibilities offered by the terrain…One can call it the coup d’œil militaire and it is inborn in great generals.” But in this case, exhibited from a staff officer. But a staff officer who is painting the picture for his commander.

Mahan does not dismiss maps as a reference. Rather he points out the limitations of a map for practical applications. The Cheetos-eating armchair generals will say it… must go out and see the terrain to really understand it! (Irony implied for emphasis.)

Mahan offered several important practices and techniques to aid the reconnoitering officer. The officer must know the minutia of unit formations – particularly how much space might be taken up by companies, battalions, regiments, and brigades in various formations; space required to perform maneuvers; time required for maneuvers; etc. Estimation of distances was (is) critical, of course. And toward that end, Mahan offered some tricks:

A very simple aid to it is the following;—Upon the stem of a lead-pencil, cut square, and held out at a uniform arm’s length from the eye, and by means of a thread attached to it and fastened to the top button-hole, let the officer mark off, on one of the edges, the length seen on it by holding the pencil upright between the eye, and a man placed successively at different distances from it, as 100, 150—1000 yards.  This will give one rough standard for practice.  Another may be made by first ascertaining the average height of certain cultivated trees, as the apple, &c.

Ibid, p.107-8

Another requirement is placing all these details in the proper perspective, in relation to the physical appearance. An accurate sketch, if you will. Toward that end, more tricks:

For getting relative positions, a contrivance for measuring angles roughly must be used.  This is done by first folding a leaf of paper across, and then doubling it along the folded edge, as if to divide it into four equal parts.  The angle between the edge of the first fold and that of the second will be a tolerably accurate right angle.  Now by cutting off carefully along the fold, one of the pieces, we obtain a quadrant or 90°; then folding this at the angle, so that the two edges will exactly coincide, we get the half of a quadrant or 45°; and so on, by successive bisections, we can mark off smaller angles.  Then making a pen or pencil-mark along each of the folds, and numbering the angles successively from 0° to 90°, we have a rough protractor, that can be used both for measuring angles and setting them off on a sketch.  To measure vertical angles, a thread with a light plummet, must be attached to the angular point.  If the object is above the horizon of the eye, we hold the protractor with the angular point from the eye, so that the plumb-line will fall along the face of the paper just touching it; then directing the top edge of the protractor on the object, so that it is just seen by the eye sighting along the edge, and the angle formed between the plumb-line and the other edge, will be the same as the angle between the line of sight and the horizon of the eye.

Ibid, p.108-9

All great stuff! And certainly tricks I would suggest you employ when next out visiting a battlefield. It will enhance your understanding (trust me… these work).

Mahan also pointed out that guides were valuable for this work. Though there are pitfalls to employing guides. All in all, the officer is still responsible for accuracy of information even when guides are employed. So… choose wisely.

But let us step back from the “practice” and more so on the application of reconnaissance. Mahan specifically singled out the reconnaissance as a means to gather information about terrain, as opposed to the enemy’s dispositions. Sure, there are armed reconnaissances. But those retain the same objective. If seeking information about the enemy, the activity, according to Mahan, is “patrolling.” With differing objectives, of course, there are different practices and procedures. We historians should take note here the differences between a reconnaissance and a patrol within the “by the book” Mahan explanation. Indeed, words have meanings. But just how far do we carry those distinctions? Often the participants used reconnaissance where they clearly meant patrol. And vice-versa. We will often interchange reconnaissance and patrol in our interpretation of those events. More to the point, if one is out poking around near the enemy does it matter if the purpose is to gather information about the lay of the land or the enemy positions… or both?

I’d say it is important to our interpretation. We might not need to call “balls and strikes” here. A clear distinction between a reconnaissance or a patrol may simply be semantics. What is more important, and what I’d impress here in closing, is to know just what objective the commander imparted to the officer conducting the reconnaissance or patrol. What body of information was requested? To what unknown was the officer directed? And to what ends did the commander hope to apply that intelligence once acquired?

Clearly the products of a reconnaissance were critical to the commander’s view of the battlefield and thus important enablers for decisions to be made. A good reconnaissance made for a good decision… or at least set up a sound decision. So it is right for us to evaluate and assess the effectiveness of a reconnaissance, not only to the quantity and quality of the information gathered, but the relevance of that information to the operation it supported.

That said.. I want to see lead pencils and folded paper next time we are out on the battlefield!

Published by Craig Swain

"Historical marker hunter" and Civil War enthusiast.

One thought on “Gettysburg, Day 2: The Services Demanded of a Reconnoitring Officer

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: