Civil War Views: Battery Martin Scott

This week's "Civil War Views" takes another look at the strategic Potomac River crossing of Chain Bridge. The defenses around the bridge became the subject of many wartime photographs and sketches. Aside from a lower battery at the Washington end of the bridge, another gun emplacement, known as Battery Martin Scott, occupied the heights immediate above. The battery was initially composed of two 32-pounders and one 8-inch seacoast howitzer mounted en barbette. Two 6-pounder rifled guns apparently replaced these three artillery pieces.

A few months ago, I discovered that the New York Public Library has made available a collection entitled, Sketches for Frank Leslie's Illustrated Newspaper : 138 original drawings of the Civil War by staff artists, 1861-1864. This set of drawings contains many fascinating images of Washington and environs during the early days of the Civil War. Among the drawings is this sketch by Arthur Lumley of Battery Martin Scott:

"High Battery at the Chain Bridge" (courtesy of New York Public Library)

As my friend and fellow blogger Craig Swain has pointed out, the three guns depicted here aren't very precise renderings of the actual armaments at the battery. Below the battery, the wooden span of Chain Bridge crosses the Chesapeake & Ohio Canal and the more distant Potomac River. A mule team pulls a boat along the canal. The gun position offers a commanding view of the Virginia shoreline and hills. Incidentally, Forts Marcy and Ethan Allen protected the approaches to Chain Bridge on the Virginia side. They cannot be seen here, but sat on the hills opposite the battery.

Lumley's sketch appears as an engraving in the November 9, 1861 issue of Frank Leslie's:

(courtesy of archive.org)

The paper said the following about the illustration of Battery Martin Scott:

WAR is a fearful and wonderful teacher of topography. Places and objects which a few months ago were known only to travellers, or those dwelling on the spot, are now "familiar as household roads." Washington and its adjacent localities  are to the majority of readers now as well known to them as to their denizens. Among the more prominent spots is the Chain Bridge, which crosses the Potomac river at the Little Falls, about five miles above Washington City. It is the direct route from the camp at Tenellytown and Georgetown to Lewinsville and Langley, and is consequently a position of much importance. Our readers will perceive that the National Government has erected a powerful battery on the Maryland side, so as to sweep with utter destruction any hostile force. Now that the Federal Capital is safe, we trust Kentucky, Missouri and Tennessee will be rescued from the rebel hordes, whose presence is unwelcome to the people of those States as it is humiliating to the National cause. (at 389-90.)

Today, I'd venture to speculate that once again, few outside the Washington area know the Chain Bridge! But Lumley's sketch reminds us of  the importance of such places over 150 years ago. So the next time you cross the river there, whether because you commute across the bridge daily, or because you are on a vacation in the area, think back to the sketch and engraving as you look up at the bluffs overlooking the Potomac.

Source

Benjamin Franklin Cooling III & Walton H. Owen II, Mr. Lincoln's Forts: A Guide to the Civil War Defenses of Washington (2010 ed.);  Frank Leslie's Illustrated Newspaper, Nov. 9, 1861; OR, 1:21:1, 911.

Civil War Views: Lower Battery at Chain Bridge

As readers may have noticed, things are a bit "quiet along the Potomac" here on the blog! With a newborn and increased responsibilities on the home front, the time I have for research and writing each night has dwindled considerably. That said, I have many new topics in the pipeline, and much of the related research is substantially completed, so I hope that I will be able to post some original, in-depth content here as we head into the spring and summer. In the meantime, I am launching a new visual series on the blog called, "Civil War Views."

I've recently come across some amazing drawings and photographs of wartime Washington, DC and Northern Virginia. It seems that every day that the Library of Congress, the National Archives, and other institutions are making more and more visual content available on the Internet. Rather than just post a newly discovered image on Facebook or Twitter, I felt it would be nice to offer a little context about the photograph, sketch, or engraving in a good, old-fashioned blog post! So now, without further ado, here is the first installment. . . .

I've written extensively about Chain Bridge over the years. Many of my posts have focused on the defenses that the Union Army erected to protect this key Potomac River crossing. I particularly like this relatively obscure photograph of the Lower Battery at Chain Bridge:

"Battery at Chain Bridge, Washington, D.C. 1862" (courtesy of the Library of Congress).

The photograph shows the battery that was established in 1861 on the Washington side of Chain Bridge. Gun crews pose next to a 12-pounder howitzer (l) and 24-pounder howitzer (r). (Thanks to my friend and fellow blogger Craig Swain for helping to verify!)  The artillery is positioned to fire through embrasures in the earthwork. A few soldiers stand guard, while others mill around at the end of the bridge. The Chesapeake & Ohio Canal is visible to the right side of the photograph. Incidentally, another gun emplacement, known as Battery Martin Scott, was located on the bluffs above the battery pictured here. More on that one in a future Civil War Views post!

Source

Benjamin Franklin Cooling III & Walton H. Owen II, Mr. Lincoln's Forts: A Guide to the Civil War Defenses of Washington (2010 ed.).

Passing Through the Old Stomping Grounds, July 1864

Following Jubal Early's defeat at the gates of Washington in July 1864, the Army of the Potomac's VI Corps pursued the Confederates westward to the Shenandoah Valley. Among the Union ranks were men who had spent the first winter of the war at Camp Griffin near Lewinsville, Virginia. They belonged to various units, including the 5th Wisconsin, 7th Maine, 43rd New York, 49th New York, 49th Pennsylvania, and 77th New York, as well as the famed First Vermont Brigade. My ancestor, Pvt. William Baumgarten of Co. K, 102nd Pennsylvania also marched with them. He had only joined the army in March 1864, but had already seen his share of horrific combat during the Overland Campaign.

A stereoscopic view of the 43rd N.Y. at Camp Griffin (courtesy of Wikipedia).

July 20-21, 1864: The Valley to Goose Creek

After suffering defeat at Rutherford's Farm on July 20, Early withdrew up the Valley to Fisher's Hill. The Federal commander, Gen. Horatio Wright, considered the Confederate threat eliminated and ordered the VI Corps and the rest of his force to return to Washington. There the Union soldiers could rest, resupply, and await further orders. (OR, 1:37:2, 419-20.)

Gen. Horatio Wright took command of the VI Corps following Gen. John Sedgwick's death at Spotsylvania (courtesy of Wikipedia). He led his men to the defense of Washington and battled Early at Ft. Stevens.

The VI Corps, along with elements of the XIX Corps, set out during the evening of July 20 from their position near Berryville. The Second Division, including William and the 102nd Pennsylvania, took the lead position in the VI Corps' line of march. [1] Headquarters directed that "[t]he troops will be made to understand that their rations must last them until they reach Washington." (OR, 1:37:2, 406.) After wading across the Shenandoah River, the men pressed on through Snicker's Gap and marched the entire night in wet clothes, taking "brief halts for coffee." (Benedict 492.)

As the sun rose over the Northern Virginia countryside, the columns continued to snake along the turnpike. The tired men of the the 49th Pennsylvania decided to stop in Hamilton for breakfast. According to one diarist from the regiment, "the citizens waved the stars and stripes as we passed through the little village; our bands played and our colors were unfurled." (in Westbrook 213.)

In the afternoon the VI Corps marched through Leesburg and halted near Goose Creek. Here the soldiers rested their sore feet and camped for the night. Those lagging behind on the march were not so fortunate. As the diarist from the 49th Pennsylvania wrote that day, "[John] Mosby is reported in the rear, gobbling up stragglers." (in Westbrook 213.)

July 22, 1864: Goose Creek to Difficult Run & Environs

The wagon train got underway at 4 a.m. on July 22, followed by the VI Corps and the XIX Corps. The day's route took the troops along the Leesburg-Alexandria Turnpike (today's VA-7). Seeking to protect his columns, Wright ordered that "[t]he cavalry under Colonel [Charles Russell] Lowell. . . be kept well out to the front, flanks, and rear, and endeavor to break up the guerrilla parties in the line of march." (OR, 1:37:2, 412.)

The divisions filed past Dranesville, where the Lees burg-Alexandria Turnpike intersected the Leesburg-Georgetown Turnpike (today's VA-193). Both roads led towards Washington. To avoid any confusion among his commanders, Wright made clear in his orders that the two corps were to continue on the Leesburg-Alexandria Turnpike.  

After another long march through heat and dust, the Federal force halted for the night in the vicinity of Difficult Creek. Some of the troops progressed as far as Freedom Hill and Peach Grove Post-Office (today's Tysons Corner) before setting up camp.

July 23-26, 1864: Lewinsville, Langley, and Beyond

The next day, July 23, followed a similar pattern. The two corps began their march around 4 a.m. Before long, they would enter the tiny hamlet of Lewinsville (part of today's McLean). Their route took them past the battlefields where some of the men had fought J.E.B. Stuart in September 1861. They also moved over the very ground once occupied by Camp Griffin. Some of these soldiers had lived here during winter 1861-62 as part of Gen. William F. "Baldy" Smith's division. The diarist from the 49th Pennsylvania observed a few differences from those early days:

 [O]ld Camp Griffin has been changed into contraband farms, and our old parade ground is growing a crop of corn. . . . (in Westbrook 213.) [2]

Union Army map showing Lewinsville and vicinity (courtesy of Library of Congress). Wright's men took the road from Peach Grove P.O. (far left), through Lewinsville (center), to Langley (far right). There the VI and XIX Corps picked up the Leesburg-Georgetown Turnpike to Chain Bridge. Camp Griffin sat on the Mackall, Johnston, and Smoot properties and the surrounding land. Living in this area, I am moved to think that 150 years ago, my ancestor was marching past my very neighborhood on his way to Chain Bridge. How the world is small, even across time!

Wilbur Fisk of the 2nd Vermont even located his former campsite. As he wrote in a letter on August 8, 1864:

There was the same excavation that we had made for the floor of our tent, the same fire-place and chimney and the same log basement. There was my old bedstead made of barrel staves nailed to two poles, and there was my old stool, which I remember used always to be in the other boys' way and which was always a reproach upon my woeful lack of ingenuity. I found too, the identical cup which has served me with coffee many times -- a good one once, but now rusty and half filled with dirt; and there were many other things that I saw around that little spot, uninteresting to others though quite interesting to me. . . . .  An eventful  season of war and strife has passed since we left that ground, and many that were with us then have been laid low by rebel hands; but peace comes not yet. Our regiment was full and strong when it left Camp Griffin, but not one-tenth of those men are with us now. (in Rosenblatt 243-44.)

Continuing along the pike beyond Langley, the VI Corps headed in the direction of Chain Bridge. Some of the men entered familiar territory once again -- on the high ground near the bridge was where soldiers under Gen. Smith had established Camp Advance and started construction of defensive works in September 1861.

Proceeding down a steep hill, Wright's corps reached Chain Bridge, crossed the Potomac, and halted in a rough line stretching from from Battery Vermont to Fort Gaines and Tennallytown. The general immediately took steps to ensure that his corps received adequate supplies. He urged his commanders to "have the wants of their men supplied as rapidly as practicable." (OR, 1:37:2, 425.)

In the end, Wright spent very little time around Tennallytown. Instead of returning to the front before Petersburg, he was dispatched to deal with a new threat from Early. By the morning of July 26, the men were once again on the move. They broke camp and marched that day to Rockville. The campaign against Early was entering a new and prolonged phase.

Postscript

The march of the VI Corps through Lewinsville and Langley was a bittersweet homecoming for some. By summer of 1864, the war had taken a terrible toll, and many soldiers never lived to see the old campgrounds for a second time. Others had left the ranks due to wounds, disease, or the end of enlistment. The survivors also looked upon a landscape that had undergone a revolutionary transformation. In place of picket lines, drills, and military parades were contrabands, marking the transition from slavery to freedom. A return to the "stomping grounds" of 1861-62 symbolized just how far the war had progressed since those early days of relative calm and innocence, before the massive bloodletting and the fight for emancipation.

Notes

[1] Incidentally, William received a head wound in skirmishing around Snicker's Gap a few days before and may possibly have made the trip by ambulance. The exact timing and circumstances of William's wounding is somewhat uncertain based on available sources.

[2] By summer 1864, the contraband farm, Camp Wadsworth, sat on land where Camp Griffin was once located. (See my post here for more information.) Camp Beckwith, another contraband farm, sat north of the village of Lewinsville.


Sources

George Grenville Benedict, Vermont in the Civil War, Vol. 1 (1886); Butler County PAGenWeb, "Genealogical Inquiries" (contains excerpt on Wm. Baumgarten from 1889 book, Presidents, Soldiers and Statesmen, Vol. 1); John H. Niebaum, History of the Pittsburgh Washington Infantry: 102nd (Old 13th) Regiment Pennsylvania Veteran Volunteers and Its Forebears, 1792 to 1930 (1931); Official Records, 1:37:1, 406-457 & 1:37:2, 272 et seq.; Emil & Ruth Rosenblatt, Hard Marching Every Day: The Civil War Letters of Private Wilbur Fisk (1992 ed.); Robert Westbrook, History of the 49th Pennsylvania Volunteers (1897).

A Surprise Visit to Battery Parrott

A few weeks ago I had the pleasure of attending a reception at the residence of the Belgian Ambassador to the United States. Located along Foxhall Rd., N.W. in Washington, this ornate home sits atop the heights dominating the Potomac River near Chain Bridge. Imagine my surprise when I discovered that that the property was the site of Battery Parrott, part of the defenses of Washington during the Civil War. In fact, the Belgian Embassy website even discusses the history associated with the location.

The Union Army erected Battery Parrott in 1862 on land belonging to local widow Ellen King. The battery was named after Robert P. Parrott, a former captain of ordinance and inventor of the Parrott gun.  Battery Parrott was equipped with two 100-pounder Parrott rifles. Gen. John G. Barnard, Chief Engineer for the Department of Washington, later called Battery Parrott one of the "most perfect and complete" batteries in the defenses of the nation's capital. (Barnard 72-73.) Along with Batteries Cameron and Kemble, Battery Parrott swept the Virginia side of the Potomac from Chain Bridge and Forts Marcy and Ethan Allen to Fort DeKalb (Fort Strong).


The remaining earthworks of Battery Parrott are plainly visible in the backyard of the Belgian Ambassador's Residence. The massive Parrott guns were mounted en barbette behind the parapet.

Battery Parrott was garrisoned at various times by companies from the 1st Maine Heavy Artillery, the 1st New Hampshire Heavy Artillery, and the 9th New York Heavy Artillery. Company K of the 1st Maine Heavy Artillery served the longest at the battery, from August 1862 until being sent to the front during the Overland Campaign in May 1864. Writing to Chief of Staff Henry W. Halleck about the state of Washington's defenses in spring 1864, Gen. A.P. Howe, Inspector of Artillery, observed:

Battery Parrott, Capt. Frederic E. Shaw commanding.–Garrison, one company First Maine Heavy Artillery–1 commissioned officer, 1 ordnance-sergeant, 46 men. Armament, two 100-pounder Parrots. Magazines, one; dry and in good order. Ammunition, full supply and serviceable. Implements, complete and serviceable. Drill in artillery, fair. Drill in infantry, fair. Garrison is sufficient. (in NPS at Vol. I, Appendix E.)

As with nearly all of the forts and batteries around the nations capital, Battery Parrott saw no action during the Civil War.

Photo of a 100-pounder Parrott, this one taken at Ft. Totten outside Washington (courtesy Library of Congress)

At the end of hostilities in 1865, the Union military offered King wood and other materials from the battery as compensation for the occupation of her land. The widow refused at first, but relented in October 1865, accepted the in-kind compensation, and signed a release discharging any future claims against the U.S. Government. King nevertheless filed a claim for rent and the taking of timber in May 1874. Despite the earlier release, King prevailed and was awarded compensation by the U.S. Treasury Department in 1875 and 1876.

Detail from 1865 War Department map of the defenses of Washington showing the position of Battery Parrott (center), as well as other features, including Batteries Cameron and Kemble, Chain Bridge, Ft. Marcy, Ft. Ethan Allen, and Ft. Strong (courtesy of the Library of Congress).

The position of Battery Parrott (blue pin) indicated on a modern map of Washington, DC and Virginia. (See here for a larger map.)

Sipping on a Belgian beer and looking out at the earthworks behind the ambassador's house, I couldn't help but chuckle. Things are sometimes ironic like that in Washington. One hundred and fifty years ago, boys from Maine tramped across this very land, while 100-pounder guns stood guard against the possibility of Rebel incursions, however remote. Now internationally-minded professionals were mingling and eating hors d'oeuvres, most oblivious to the importance of the site during our nation's most trying ordeal.

Sources

John G. Barnard, A Report on the Defenses of Washington (1871); Benjamin Franklin Cooling III & Walton H. Owen II, Mr. Lincoln's Forts: A Guide to the Civil War Defenses of Washington (2010 ed.); Historic Preservation Review Board, Government of the District of Columbia, Application for Historic Landmark or Historic District Designation for the Scheele-Brown Farmhouse (2013); National Park Service, A Historic Resources Study: The Civil War Defenses of Washington, Parts I & II (2004); Official Records, Series 1, Vol. XXV, Pt. 2, at 187 (1889).

Improving Historical Interpretation at Ft. Ethan Allen

A couple years ago I took a tour of the Civil War forts of Arlington.  During the excursion, I learned that the county would be making much-needed improvements to the site of Ft. Ethan Allen, but timing seemed uncertain.  Built in the fall of 1861, the fort guarded the approaches to the strategic crossing of the Potomac River at Chain Bridge.  Today several earthworks survive and are preserved as part of Ft. Ethan Allen Park.  Unfortunately, visitors will find little in the way of interpretation aside from a couple historical markers.  (See here and here.)  All of this is about to change.

One of the existing historical markers at the entrance to Ft. Ethan Allen Park.  The remains of the fort's southern face can be seen in the background.

In 2011 Arlington provided $473,000 in funds to develop interpretive features at Ft. Ethan Allen Park.  The Arlington County Department of Community Planning, Housing, and Development has responsibility for the project, and the plans for the site were recently posted on-line.  According to a presentation by Arlington County, construction and installation of the new interpretative elements should be complete by late November 2013.  Arlington will recreate one of the fort's gun emplacements, complete with a 20-pounder Parrott.   Several markers will be placed across the site to explain different aspects of the fort, including the existing remains of the guard house, bombproof, and powder magazines.  The county will also install a 3-D model of Ft. Ethan Allen along with a memorial to the soldiers who garrisoned the fort.  If what Arlington did at Ft. C.F. Smith is any guide, we should be very excited to see the final results.

Remains of the bombproof at Ft. Ethan Allen

Arlington commissioned the project management firm Versar to conduct an archaeological survey of the impact of the planned improvements on the historic site.  The archaeologists investigated three locations where the county intends to place the interpretive features.  According to Versar's final report, the team "found little new evidence of Fort Ethan Allen’s past. . . ."  Unfortunately, "much of the ground surface has been significantly altered during the course of the 20th century."  The archaeologists discovered a few Civil War artifacts, including lead bullets, but "all of these appeared to have been moved around in the years since they were initially dropped or lost."  They also located the probable location of the fort's well, which was filled with rubble sometime last century.  Versar considered that "[t]he most significant surviving elements of the original fort appear to be the massive remains of the earthworks themselves clearly visible on the surface."  The report concluded that the interpretive elements "were unlikely to disturb any intact cultural deposits or features" and recommended that the 3-D model and memorial "be placed and constructed to avoid the well. . . ."* 

The improvements to Ft. Ethan Allen are a welcome addition to the park, which currently suffers from a lack of sufficient interpretation when compared to other local sites like Ft. C.F. Smith in Arlington and Ft. Ward in Alexandria.  Starting this fall, Ft. Ethan Allen will become an even more compelling destination in Northern Virginia for those interested in the defenses of Washington.  I will be sure to keep readers informed as the project at Ft. Ethan Allen progresses throughout the year.

Note

*One of the best parts of the report is the digital recreation of Ft. Ethan Allen and environs.  (See p. 14.)  I only wish I had such computer graphics skills!

A "Mystery" Solved: The Blockhouse at the Chain Bridge

A few weeks ago I wrote about a wartime photograph of a blockhouse at the Chain Bridge over the Potomac that was published in Miller's Photographic History.  Something about the picture just didn't add up, and the documentary evidence failed to confirm with any certainty that the photograph was what the caption in Miller's said it was.  As I wrote, "the complete story behind the 'blockhouse at the Chain Bridge' remains a mystery."  Thanks to a few knowledgeable readers, it didn't remain a mystery for very long.

Within days of posting the story about the blockhouse at Chain Bridge, Chuck Siegel, Debbie Robison, and Keith Yoder contacted me.  All of them wrote to say that the photograph in Miller's actually depicts the Orange & Alexandria Railroad (O & A R.R.) bridge over Bull Run.  Their comments and emails referred me to numerous pieces of photographic evidence to prove that Miller's Photographic History had gotten it all wrong.  (Incidentally, Chuck Siegel maintains a website dedicated to O & A R.R.; Debbie Robison is a Fairfax County History Commissioner who writes a blog on Northern Virginia history.)

Debbie sent me a reference to a National Archives copy of the photograph in Miller's, entitled "Bridge and blockhouse built by U.S. engineers, ca. 1860-ca. 1865."  I was struck by what I saw on the high resolution digital copy of the image.  Such magnification was not possible with the versions of the photograph that I had previously examined.  An enlargement of the photograph clearly shows railcar wheels and axles scattered at the bottom of the bridge near the water's edge.  Railroad tracks are also visible running across the bridge.  Chain Bridge was not a railroad bridge, and sat nowhere near a railroad!  The topography in the photograph also matches that seen in other images of the railroad crossing at Bull Run.  (See here and here, for example.)   Likewise, the distinctive stone abutment that appears here looks like the one seen in other photographs of the Bull Run Bridge.  After searching the Library of Congress collection of Civil War photographs, I located a copy of the same photograph entitled, "U.S. Military Railroad Bridge, Bull Run, Va. Orange and Alexandria R.R."  This find confirmed the actual identity of the bridge published in Miller's.

"Bridge and blockhouse built by U.S.engineers, ca. 1860-ca. 1865" (courtesy National Archives, ARC Identifier #524695). The railroad bridge over Bull Run, located near Union Mills, was rebuilt at least seven times during the course of the Civil War.

Detail of the above photograph showing railcar debris around the bridge abutment.  Note also the railroad tracks crossing the bridge.

Another photograph of the same location, seen below, looks across the railroad bridge from the side where the blockhouse was situated.  The people gathered there, including women and children, appear to match the individuals shown in the photograph from Miller's.  It is likely that these two photographs were taken on the same day.

"Bridge, ca. 1860-ca. 1865" (courtesy of National Archives, ARC Identifier #529324).  Compare the group of persons in this photograph with the close-up from the photograph above.

This photograph depicts the construction of the truss bridge over Bull Run in April 1863 and provides yet another view of the topography at the crossing:

"Part of construction corps building new military truss bridge across Bull Run, April 1863" (courtesy of Library of Congress).

Other photographs show the blockhouse that was constructed on a bluff to the northeast of the O & A R.R. bridge on the Fairfax County side of Bull Run.  Such structures were designed to guard railroad bridges and other critical locations against attack by Confederate partisans operating in the area. 

"Bridge and block house on Orange and Alexandria R.R. near Bull Run, Va."  (courtesy of Library of Congress).  This photograph looks east across Bull Run.  The truss bridge is visible above and to the left of the cabins.  Another blockhouse was apparently built to the southwest of the bridge in Prince William County.

"R. R. (i.e. Railroad) bridge across Bull Run. O. & A. R.R." (courtesy of Library of Congress). Another view of the railroad bridge and blockhouse, taken farther downstream.

A current view of the bridge abutment on the Fairfax County side of Bull Run (courtesy of Historical Marker Database).  A Norfolk Southern bridge now crosses the stream to the left of the original location.  According to Chuck Siegel, the imprint of the blockhouse also remains, but is now overgrown with underbrush.

The skeptic in me couldn't take that picture in Miller's Photographic History at face value given what I know about Chain Bridge and the defenses of Washington.  I'm glad that readers responded to my original post and helped to set the record straight.  Now if we can just get that caption in Miller's classic work corrected! 

Sources

George B. Abdill, Civil War Railroads: A Pictorial Story of the War Between the States, 1861-1865 (1961); National Register of Historic Places Nomination Form, Orange and Alexandria Railroad Bridge Piers (1989).

Thanksgiving 1862 in the Defenses of Washington Near Chain Bridge

This week as we prepare to celebrate Thanksgiving, I wanted to offer readers a brief look into how Union soldiers defending the nation's capital spent the holiday in 1862.  One hundred and fifty years ago, the area around the strategic crossing of the Potomac at Chain Bridge was home to several regiments.  Camp life offered little excitement, and the men spent their days drilling, performing picket duty, or working on the forts and earthworks.  Thanksgiving provided the soldiers with a welcome respite from the daily grind in front of Washington.

The 118th New York, nicknamed the "Adirondack Regiment," was composed of three-year volunteers from Clinton, Essex, and Warren Counties.  Organized in Plattsburgh, the regiment left for Maryland in early September 1862, but by November 1862 had moved to the area around Ft. Ethan Allen and Chain Bridge.  Governor Edwin Morgan of New York proclaimed Thursday, November 27, as a day of thanksgiving, and the men of the 118th New York took the time to observe the holiday like their friends and family back home.

The soldiers surely were thankful for the "[f]ine and warm" weather on the twenty-seventh.  (Cunningham 34.)  Only the week before the New Yorkers had endured cold, rainy conditions that left 1st Lieutenant John Cunningham "quite wet and 'shivery.'"  (Cunningham 34.)  The regimental chaplain led the boys of the 118th in a service of thanksgiving.  Cunningham and the others also enjoyed a relatively hearty meal.  As the young officer wrote in his diary, "[f]or dinner had bread, salt beef, fried bread, pickles, coffee, cheese and more bread, with bread and molasses for dessert."  (Cunningham 34.)  The entire day left Cunningham "happy and thankful."  (Cunningham 34.)

"Thanksgiving in Camp," Harper's Weekly, Nov. 29, 1862, by Winslow Homer (courtesy of Wikipedia)

The 127th Pennsylvania, known popularly as the "Dauhpin County Regiment," consisted of nine-month volunteers from Dauphin, Lebanon, and Adams Counties.  The regiment headed to Washington in August 1862 and soon took up a position not far from Ft. Ethan Allen and Chain Bridge.  In October, the regiment moved briefly to another spot about three miles from Ft. Ethan Allen, before receiving orders to return closer to the fort.  Col. William Jennings of the 127th christened this place "Camp Dauphin."  According to a history of the 127th Pennsylvania, the camp "was pleasantly located in a young peach orchard, on level, or slightly sloping ground, and was an ideal spot." (History of the 127th Regiment 154.)  The soldiers thought that this location would serve as their home for the winter and began to construct log cabins there.

Pennsylvania Governor Andrew Curtin, like his counterpart from New York, issued a proclamation declaring November 27th as a day of thanksgiving.  On November 26, Lt. Col. Hiram C. Alleman issued a special order "directing" that the next day "should be observed in strict accordance with the Proclamation of Gov. Curtin."  (Pa. Daily Telegraph, Nov. 29, 1862.)  The order was read to the men at evening dress parade. 

Rev. John Gregg, the regimental chaplain, described how the regiment began Thanksgiving Day in a letter to the Pennsylvania Daily Telegraph of Harrisburg on November 27:

We had a ceremony this morning at 10 o'clock, which was not only interesting, but highly appropriate to the occasion.  The regiment was formed on parade ground, and the Colonel designated company B to escort the colors.  The regiment was then formed into a hollow square, the Governor's Proclamation was read by [the adjutant], and a prayer suitable to the occasion was offered by the Chaplain.  After singing the doxology, and executing some military manoeuvres, both the religious and military exercises closed.  (Pa. Daily Telegraph, Nov. 29, 1862.)

Gregg added that the regiment "had neither company or battalion drill during the day, and the boys enjoyed themselves to their heart's content."  (Pa. Daily Telegraph, Nov. 29, 1862.)  Whether liquor was consumed, the reverend did not say!  Gregg took the opportunity to tell readers that "[t]he health of the men is improving and the boys generally seem to be in good spirits."  He was also "glad to inform the friends of religion, that most of those who profess faith in Christ, have formed themselves into a Christian body. . . ."  (Pa. Daily Telegraph, Nov. 29, 1862.)  Gregg "hope[d] that much good will be accomplished by the united efforts of the members of this body, composed as it is of members of the many Christian denominations represented in this regiment."  (Pa. Daily Telegraph, Nov. 29, 1862.) 

The 127th Pennsylvania would soon leave the defenses of Washington and march to join the Army of the Potomac along the Rappahannock.  As part of the Second Corps, the regiment fought at the Battle of Fredericksburg on December 13 and suffered more than a hundred casualties.

These recollections of Thanksgiving in camp near Chain Bridge demonstrate the central role that religion played in observing the holiday 150 years ago.  (The separation of church and state seemed a bit less of a concern then too.)  Of course, the soldiers also looked on the day as an opportunity to relax and indulge, just as we do today.  And so, as we prepare to enjoy turkey with all the fixings, I'd like to wish all of my readers a Happy Thanksgiving!

Editorial Note to Readers

I just wanted to let everyone know that due to an increasingly intense and unpredictable work schedule between now and Christmas, the frequency of posts is about to drop.  I'll make my best efforts to get something up in a few weeks, starting with a follow-up on that Chain Bridge blockhouse story.

Sources

Committee of the Regimental Ass'n. of the 127th Pa., History of the 127th Regiment, Pennsylvania Volunteers (1902); John L. Cunningham, Three Years with the Adirondack Regiment (1920); New York State Military Museum and Veterans Research Center, "118th Infantry Regiment: Civil War: Adirondack Regiment;"  N.Y. Times, Oct. 2, 1862; Pa. Daily Telegraph, Nov. 29, 1862; George E. Reed (ed.), Pennsylvania Archives, Fourth Series, Vol. VIII: Papers of the Governors, 1858-1871 (1902); Richard A. Sauers, Advance the Colors: Pennsylvania Civil War Battle Flags, Vol. II (1991).

The Chain Bridge Defenses: A Mysterious Blockhouse

Following a recent trip to the Falls Church Library, I decided to swing by my local Books-A-Million on the way home.  As I was browsing the bargain bin, a Blue & Gray Press reprint of Volume 5 of Francis T. Miller's famous, The Photographic History of The Civil War, caught my eye.  This volume focuses on forts and artillery and includes a chapter on "Defending the National Capital."  A photograph on page 75 entitled, "Blockhouse at the Chain Bridge, Above Georgetown," really peaked my curiosity.  I've read a lot about the Chain Bridge and the Civil War defenses of Washington, but had never come across any mention of a blockhouse being built at the bridgehead.  I was determined to learn more about the subject of this unique photograph. 

Photograph and caption from p. 75 of Miller's The Photographic History of The Civil War, Volume 5: Forts and Artillery (courtesy of Perseus Digital Library, Tufts University)

The caption for the photograph in Miller's Photographic History includes no indication of when it was taken or who took it.  The image depicts a small group of persons gathered at the end of the Chain Bridge below the blockhouse.  At least one woman is standing there, along with a few children.  Given the format of digital reproduction that I found, it is difficult to magnify the photograph on a computer to see more detail. 

Virginia Side or D.C. Side?

During the Civil War, the D.C. side of the Chain Bridge crossed low over the Chesapeake & Ohio Canal before meeting the shore (see photograph below), while the Virginia side passed high over the Potomac River and ended abruptly at a steep bank.  (Barnard 80.)  The bridge in Miller's book appears to hit the shore at the river, or Virginia, end.  A modern photograph of the same location, which has not changed much since the war, supports this conclusion (see below). 

A wartime view of the Georgetown/D.C. end of the Chain Bridge (courtesy of Library of Congress).  Note the Chesapeake & Ohio Canal immediately below the bridge.



Contemporary view of the Chain Bridge and the Potomac at the Virginia shoreline, looking south (courtesy of Wikipedia).  The curve in the river and the shape of the palisades on the Virginia side appear to match the same features in the photograph from Miller's Photographic History.

At the time of the war, the ruins of an industrial brick building (or buildings) stood on the south side of the Virginia end of the bridge.  A lone chimney also rose above the Chain Bridge around the same area (see the series of photographs below).  Both of these features appear to be missing from the photograph in Miller's classic work.  The ruins were likely situated farther down the road, outside the frame of the photograph.  At some point when I have more time I'd like to hike around the site to get a better idea of where the blockhouse and ruins were possibly located in relation to the old bridge.

Ruins of an old manufacturing building on the Virginia side of the Chain Bridge (courtesy of Library of Congress).

Another view of ruins near the head of the bridge on the Virginia side (courtesy of Wikipedia).



View from heights above the bridge, showing the ruins of a brick chimney (courtesy of Library of Congress).  The remnants of the brick industrial building are visible below, to the right of the Chain Bridge.

A Blockhouse?

During the war, the Chain Bridge was one of three strategic crossings of the Potomac River near Washington.  As Gen. John G. Barnard, Chief Engineer for the Department of Washington, recalled, "The possession of the Chain Bridge communication with the opposite shore of the Potomac, incidentally important in a defensive point of view, was essential to our operations in Virginia and to the prestige of our arms."  (Barnard 47.)  Accordingly, the Union Army constructed several works on both sides of the Potomac to protect this vital link between Washington and Virginia.  In the Old Dominion, Forts Marcy and Ethan Allen, along with a system of rifle trenches and batteries, served as the main defensive works.  On the D.C. side, a battery of field guns sat at the end of the bridge; Battery Martin Scott occupied the heights above.  Batteries Vermont, Kemble, Parrott, and Cameron also swept the land around Chain Bridge in Virginia from their dominant positions on the other side of the river.*

The Union Army constructed several blockhouses around the nation's capital, but commonly-consulted sources on the defenses of Washington do not list a blockhouse as part of the works at the Chain Bridge.  Three blockhouses were erected on the Virginia side of the Aqueduct Bridge (near today's Key Bridge).  Blockhouses were also built near Alexandria at Hunting Creek and on the Leesburg-Alexandria Turnpike around Ft. Ward.  In November 1864, the Union Army began to erect a series of picket posts, including blockhouses, that stretched from Prospect Hill on the Leesburg-Georgetown Turnpike (a few miles from the Chain Bridge) to Vienna, Fairfax Courthouse, and Fairfax Station.  

A wartime report on Washington's defenses offers a clue as to the construction of a blockhouse at the Chain Bridge.  On October 25, 1862, Secretary of War Edwin M. Stanton appointed a Commission to examine the adequacy of Washington's defenses.  Barnard served on the Commission along with other military experts, including Quartermaster General Montgomery Meigs and the Chief of Engineers, Gen. John G. Totten.  In December 1862, the Commission offered its recommendations.  After reviewing the state of the defenses around the Chain Bridge, the Commission concluded:

[S]ome defensive arrangements are necessary immediately about the head of the bridge; probably two or three small works, or, perhaps, block-houses would suffice.  (OR, 1:21, 909.)

Several months later, on May 22, 1863, Barnard complained to the head of the Department of Washington, Gen. Samuel P. Heintzelman, that he was running low on funds to hire workers for the improvements recommended by the Commission.  As to the Chain Bridge, he explained:

. . . there remains much to be done, and I will continue a force of mechanics, with some laborers, provided I can have the assistance of the troops.  (OR, 1:25:2, 513.)

However, a few weeks later, on July 7, 1863, Barnard reported to Col. J.C. Kelton, the Assistant Adjutant-General:

The work has been prosecuted with all the vigor the means at my disposal would admit. Although the winter season was most unfavorable for such work, and with the limited amount of money available, as well as with regard to economy, it was not deemed advisable to employ very large gangs of hired laborers, yet, by aid of the troops, working whenever the weather and state of the ground would permit, the most essential works recommended by the commission, such as . . . the additional works at the Chain Bridge. . . were all pressed forward, so as to be in a condition, if not complete, at least of efficiency, for their uses, with the return of the season, when active field operations might throw Washington upon its defenses.  (OR, 1:27:3, 596.)

Barnard's correspondence indicates that despite resource constraints, the Union Army completed or made substantial progress on the recommended works at the Chain Bridge -- which possibly included one or more blockhouses -- by mid-summer of 1863.  However, in his post-war report on the defenses of Washington Barnard elaborated on the fate of the blockhouses at the Chain Bridge:

It has been seen that the Commission recommended that some defensive arrangements should be made immediately about the head of the bridge, suggesting two or three small works or block-houses.  This recommendation, though always contemplated, was never complied with. Doubtless, however, this interior and limited inclosure of the bridge-head is a necessary and important part of all extensive "tetes de pont." (Barnard 47.)

So, is Barnard wrong about the blockhouse?  After all, pictures presumably don't lie.  His report was published several years after the close of the war, and his memory may have grown a bit cloudy, particularly if the blockhouse was built following his departure from the Department of Washington in 1864.  Alternatively, the U.S. Army may have constructed the blockhouse at some point during the post-war period, and Miller's Photographic History may have erroneously classified the image as a Civil War-era one.  If that is the case, then for what defensive purposes was the blockhouse built?  After all, an active rebellion no longer threatened the river crossing at the Chain Bridge.  Another possibility is that Miller's book misidentified the photograph, and that it actually depicts another bridge and another blockhouse somewhere else that bears an uncanny resemblance to the area around the Chain Bridge.  Whatever the theory, one thing is certain -- the complete story behind the "blockhouse at the Chain Bridge" remains a mystery.

Notes

*A sub-caption to the photograph in Miller's Photographic History explains that "[the Chain Bridge] approach was defended by Forts Ethan Allen and Marcy on the Virginia side, and by Batteries Martin Scott, Vermont, and Kemble on the Maryland side of the Potomac."  (Miller, Vol. 5, 75.)

Sources

Aside from the Official Records, the following sources were useful in compiling this post:

John G. Barnard, A Report on the Defenses of Washington (1871); Benjamin Franklin Cooling III & Walton H. Owen II, Mr. Lincoln's Forts: A Guide to the Civil War Defenses of Washington (2010 ed.); Historical Marker Database, "Pimmit Run and Chain Bridge"; Francis T. Miller & E.O. Hunt (eds.), The Photographic History of the Civil War in Ten Volumes, Volume 5: Forts and Artillery (1911); National Park Service, A Historic Resources Study: The Civil War Defenses of Washington, Parts I & II (2004).

The Chain Bridge Defenses During the Maryland Campaign, Part III: Sigel Stays Put and Stands Guard

In the last couple of posts, I've followed the story of the Chain Bridge defenses around Washington in the days prior to Antietam.  During the first week of September 1862, Franz Sigel led his corps from Fairfax Court House to the vicinity of Ft. Ethan Allen.  As Gen. George McClellan moved his army across the Potomac to chase down the Robert E. Lee, he left Sigel's men, along with the corps of Fitz John Porter and Samuel P. Heintzelman, to guard the Virginia side of the river in front of the nation's capital.  By September 7, Sigel's line stretched from Ft. Marcy and Ft. Ethan Allen, near Chain Bridge, to Ft. DeKalb in present-day Arlington.

McClellan Tries to Extract Sigel and Other Reinforcements from Washington's Defenses

Before long, McClellan was asking Washington to send him reinforcements, including men from Sigel's corps and the other commands around the capital.  Generally inclined to overestimate Confederate troop strength, Little Mac was no different this time around.  He believed that Lee had "not less than 120,000 men" near Frederick, Maryland. (OR, 1:19:2, 254.)  In fact, the Army of the Potomac had around a two-to-one advantage over Lee.  (Sears, Landscape, 102.)

On September 10, McClellan wrote to General-in-Chief Henry Halleck:

At the time this army moved from Washington, it was not known what the intentions of the rebels were in placing their forces on this side of the Potomac. It might have been a feint to draw away our troops from Washington, for the purpose of throwing their main army into the city as soon as we were out of the way, or it might have been supposed to be precisely what they are now doing. In view of this uncertain condition of things, I left what I conceived to be a sufficient force to defend the city against any army they could bring against it from the Virginia side of the Potomac.  (OR, 1:19:2, 254.)*

McClellan, however, felt that "[t]his uncertainty . . . exists no longer."  (OR, 1:19:2, 254.)  The immediate danger to the capital had passed.  McClellan informed Halleck of the overwhelming number of Confederates at Frederick and warned that "if we should be defeated the consequences to the country would be disastrous in the extreme."   (OR, 1:19:2, 254.)  Little Mac pleaded for Halleck to send him more men:

Under these circumstances, I would recommend that one or two of the three army corps now on the Potomac, opposite Washington, be at once withdrawn and sent to re-enforce this army . . . . (OR, 1:19:2, 254.) 

The commander perceived little threat to Washington:

If there are any rebel forces remaining on the other side of the Potomac, they must be so few that the troops left in the forts, after the two corps shall have been withdrawn, will be sufficient to check them; and, with the large cavalry force now on that side kept well out in front to give warning of the distant approach of any very large army, a part of this army might be sent back within the entrenchments to assist in repelling an attack.  (OR, 1:19:2, 254.) 

McClellan seemed almost nonchalant about the possible capture of the nation's capital:

But even if Washington should be taken while these armies are confronting each other, this would not, in my judgment, bear comparison with the ruin and disaster which would follow a signal defeat of this army.  If we should be successful in conquering the gigantic rebel army before us, we would have no difficulty in recovering it. On the other hand, should their force prove sufficiently powerful to defeat us, would all the forces now around Washington be sufficient to prevent such a victorious army from carrying the works on this side of the Potomac, after they are uncovered by our army? I think not.  (OR, 1:19:2, 254-55.)** 

From his headquarters near Rockville on September 11, McClellan further urged Halleck:

Please send forward all the troops you can spare from Washington, particularly Porter's, Heintzelman's, Sigel's, and all the other old troops. Please send them to Brookville, via Leesborough.  (OR, 1:19:2, 253.)***

President Lincoln himself responded to McClellan's plea for additional soldiers from the defenses of Washington.  (OR, 1:19:2, 253.)  The President understood that the new recruits streaming into Washington were mixed with the three commands and worried that "[i]f Porter, Heintzelman, and Sigel were sent you, it would sweep everything from the other side of the river. . . ." (OR, 1:19:2, 253.)  Instead, he released only the remainder of Porter's Fifth Corps, which was ordered to cross the Potomac and join the Army of the Potomac in the field.  (OR, 1:19:2, 253, 255.)  Lincoln held out the possibility of future reinforcements: 

I am for sending you all than can be spared, and I hope others can follow Porter very soon.  (OR, 1:19:2, 254.)

In the end, however, Sigel's men would stay put near the Chain Bridge defenses while the Army of the Potomac tracked down and fought Lee.

"General McClellan Entering the Town of Frederick, Maryland--The Popular Welcome," Harper's Weekly, Oct. 4, 1862 (courtesy of sonofthesouth.net).

Sigel's Corps and Everyday Life in Front of Washington

During the Maryland Campaign, Sigel's corps underwent a few organizational changes.  Once McClellan took to the field with the main army, Sigel reported to Gen. Nathaniel Banks, whom McClellan had placed in overall command of Washington's defenses. (OR, 1:19:2, 202, 214.)  Under General Orders No. 129, dated September 12, the War Department officially re-designated the three corps of the former Army of Virginia, and Sigel's First Corps became the Eleventh Corps of the Army of the Potomac.  (OR, 1:19:2, 279.) 

As McClellan battled Lee at South Mountain and Antietam, Sigel's men dealt with the mundane routine of camp life.  Soldiers spent the days drilling or on picket duty.  One regiment, the 27th Pennsylvania, changed camps around Chain Bridge several times throughout September and performed picket duty in Falls Church, a few miles in advance of the defensive line.  Gen. Robert Milroy, a brigade commander in Sigel's corps, used his free time to venture into Washington City and sit for his photograph at Mathew Brady's studio.

Not surprisingly, the presence of thousands of Union soldiers from Sigel's corps had an impact on the surrounding community.  Jospeh Sewell lived in Langley, just down the road from Forts Marcy and Ethan Allen where Sigel's men stood guard.  The farmer, like other locals, was no stranger to the Union Army.  Soldiers from Gen. "Baldy" Smith's division lived on and around Sewell's farm during the first winter of the war and had taken their fair share of crops and timber from him.  In September 1862, troops from Milroy's brigade entered Sewell's property and seized thirty barrels of corn.  They also took around three acres of garden vegetables and potatoes.****  Other civilians in the area likely experienced similar losses at the hands of the Union defenders.

Gen. Robert Milroy, from the Brady National Photographic Art Gallery (courtesy of Library of Congress).  Not long after sitting for his photograph, Milroy was sent with his brigade to western Virginia.

After Antietam: Sigel Advances to Centreville and Fairfax Court House 

As the Maryland Campaign drew to a close, Sigel's men were moved forward from the defenses near Washington.  Concerned about a possible Confederate attempt to reoccupy the railroad junction of Manassas, Banks ordered Sigel to send Gen. Julius Stahel's division to Centreville on September 21.  (OR, 1:19:2, 340-41, 344-45, 351.)   A few days later, on September 25, the remainder of Sigel's corps was dispatched to Fairfax Court House to cover an expedition being made to recapture several railroad engines at Bristoe.  (OR, 1:19:2, 356, 359.)  Banks, anxious about Confederate intentions, ordered that Sigel exercise "[g]reat caution. . . to prevent surprise," keep the cavalry "well to the front and on the alert," and "report frequently the state of affairs."  (OR, 1:19:2, 356.)

Banks originally intended to have Sigel's corps "fall back to its former position" following the expedition.  (OR, 1:19:2, 359.)   Sigel's men, however, remained in and around Fairfax Court House and Centreville to act as a "corps of observation."  (OR, 1:19:2, 425, 428.)  In this new role, Sigel kept an eye on Confederate activity in Northern Virginia, but Banks made sure to tell Sigel that "if menaced by a superior force of the enemy," he was "to fall back to the lines of defense."  (OR, 1:19:2, 425.)

The Eleventh Corps eventually ended up in Stafford Court House for the winter.  Although the soldiers missed the bloody encounter at Antietam, as well as the slaughter at Fredericksburg in December, they would go on to experience their fair share of brutal combat during the remainder of the war.  The soldiers of the Eleventh Corps became a scapegoat for the Union defeat at Chancellorsville, where they earned the derisive nickname of the "Flying Dutchmen."  Their reputation also suffered at Gettysburg.  During the tense days of September 1862, however, the corps served a necessary, yet unheralded role, in guarding the nation's capital as McClellan confronted Lee.

Notes

*Stephen Sears demonstrates that this correspondence was likely sent on September 10, even though the OR indicates that it was sent the next day.  (Sears, McClellan Correspondence, 446.)

**In correspondence dated September 13, Halleck rebuked McClellan:  "[Y]ou attach too little importance to the capital. I assure you that you are wrong. The capture of this place will throw us back six months, if it should not destroy us. Beware of the evils I now point out to you. You saw them when here, but you seem to forget them in the distance. No more troops can be sent from here till we have fresh arrivals from the North."  (OR, 1:19:2, 280-81.)

*** Earlier on September 11, Halleck had even suggested to McClellan that he send forward either Sigel's or Porter's corps when another division that Little Mac had requested was unavailable. As Halleck said, "Why not order forward Porter's corps, or Sigel's?  If the main force of the enemy is in your front, more troops can be spared from here." (OR, 1:19:2, 253.)

****The Southern Claims Commission files indicate that Sewell was not granted compensation for the claims he made concerning the taking of this property by Milroy's men.  The Commission considered that the $150 claim for corn rested solely on Sewell's testimony.  The $300 claim for garden vegetables and potatoes was considered a "depredation."

Sources

Aside from the citations to the Official Records above, the following sources were useful in compiling this post:

Samuel P. Bates, History of Pennsylvania Volunteers, 1861-1865, Vol. I (1869); Stephen D. Engle, Yankee Dutchman: The Life of Franz Sigel (1993); Bradley Gottfried, The Maps of Antietam (2012); Charles V. Mauro, The Civil War in Fairfax County: Civilians and Soldiers (2006); Johnathan A. Noyalas, "My Will is Absolute Law": A Biography of Union General Robert H. Milroy (2006); Pennsylvania Daily Telegraph, Sept. 29, 1862; Stephen W. Sears (ed.), The Civil War Papers of George B. McClellan: Selected Correspondence, 1860-1865 (1989); Stephen W. Sears, Landscape Turned Red: The Battle of Antietam (1983); Southern Claims Commission File of Joseph Sewell, available at fold3.com.

The Chain Bridge Defenses During the Maryland Campaign, Part II: Sigel Adjusts His Line While the Confederates Demonstrate at Pimmit Run

Last week I examined the withdrawal of John Pope's defeated Union force following Second Manassas.  Franz Sigel's First Corps of the Army of Virginia, along with the corps of Edwin V. Sumner and Fitz John Porter, moved from Fairfax Court House to Langley.  By September 3, 1862, Sigel's men occupied the ground closest to the strategic crossing at Chain Bridge.  Porter sat not far away, around Hall's Hill, while Sumner crossed the Potomac and took up a position at Tennallytown.

As Gen. George B. McClellan divined Robert E. Lee's next move, he sent instructions through his chief of staff, Randolph B. Marcy, to ensure the adequate safeguarding of Washington's defenses.  On the morning of September 4, Sigel was told to "draw in the main line of his forces. . . so as to run from Ft. Ethan Allen toward [Porter's] right."  (OR, 1:51:1, 789.)  This shift would shorten Sigel's line and close any gaps between the two corps.  (OR, 1:51:1, 785, 789.)  

That same day, a small fight erupted about a half a dozen miles from Sigel's force near Chain Bridge.  As Lee prepared his army to invade Maryland by crossing the Potomac near Leesburg, Confederate cavalry was ordered to make a demonstration in front of the Federal lines near Washington.  On the morning of September 4,  Gen. Beverly Robertson led the 7th and 12th Virginia Cavalry and three guns from Capt. R. Preston Chew's horse artillery down the Leesburg-Alexandria Turnpike towards Falls Church.  Between Vienna and Lewinsville, the Confederates ran into Union pickets from Gen. Alfred Pleasonton's cavalry command and drove them back "after a brisk skirmish."  (OR, 1:19:1, 828.)  Robertson sent one gun and part of his cavalry to a point "near Lewinsville to prevent surprise" and proceeded with the rest of his force to a hill above Pimmit Run along the pike.  (OR, 1:19:1, 828; see also OR, 1:19:2, 176.)*  Two of Chew's guns opened on the Union troops, and the Federals soon returned fire with two guns of their own.  Around six that evening, Marcy alerted Sigel to the attack and cautioned him:

Your pickets should be on the alert, and your command at once drawn into the new position indicated to you this morning.  (OR, 1:51:1, 785.) 

Robertson's fight with the Union troops lasted until about sundown, when the Confederates spotted several regiments advancing from the direction of Falls Church.  Robertson deemed "the object of the reconnaissance. . . fully accomplished" and withdrew his men "at dark."  (OR, 1:19:1, 828; see also OR, 1:19:1, 814; OR, 1:19:2, 176-78; Harsh 67.)  Pleasonton dismissed the action as a mere "show of force to conceal [Lee's] movements on the Upper Potomac," and McClellan agreed.  (OR, 1:19:2, 178; OR, 1:51:1, 785.)

Gen. Beverly Robertson (courtesy of Wikipedia).  The cavalry commander had few fans among the top brass of the Army of Northern Virginia and was transferred to North Carolina soon after the skirmish of September 4.

Armed with intelligence on Lee's intentions, McClellan set his army in motion to pursue the Confederates in Maryland.  His entire force, however, would not go with him.  The Lincoln Administration wanted assurances that Washington would remain sufficiently protected.  For the time being, Sigel's corps would have the chief responsibility for guarding the key approaches to Chain Bridge. 

Late on the afternoon of September 6, Marcy sent an order to Sigel at Ft. Ethan Allen:

The commanding general directs that you at once place your corps in position to occupy the line extending from Forts Marcy and Ethan Allen to the vicinity of Fort De Kalb. General F. J. Porter's corps will occupy the line from Fort De Kalb to Hunting Creek, and General [Samuel P.] Heintzelman the line from Hunting Creek to the river below Fort Lyon. . . .  You will please post your pickets well out so as to give timely information of the approach of the enemy.** (OR, 1:51:793.)

Marcy emphasized in a postscript: "Forts Marcy and Ethan Allen will be intrusted to your charge, and you will please connect your pickets with those of General Porter."  (OR, 1:51:1, 793.)  The admonishment about tightening the line likely stemmed from complaints by Porter, who a few days earlier had advised Marcy to send "a staff officer along our lines, to establish the picket lines and the proper connections between corps."  (OR, 1:19:2, 179.)  Not long after Marcy sent the order to Sigel, he reassured Porter that "General Sigel will hold the forts at the Chain Bridge and connect with you."  (OR, 1:51:1, 791.)

Detail from 1862 Union Army map of Northeastern Virginia showing the area of Sigel's line from Ft. Marcy and Ft. Ethan Allen near Chain Bridge to the vicinity of Ft. DeKalb (courtesy of Library of Congress).  For a modern view of the same area, see here.

That night, the area around Chain Bridge buzzed with activity.  McClellan ordered the Sixth Corps under Gen. William B. Franklin to cross the bridge and march to Rockville via Tennallytown.  (OR, 1:51:1, 793; OR, 1:19:1, 38.).   Gen. George Sykes's division from Porter's corps was likewise instructed to proceed to Tennallytown.  (OR, 1:51:1, 791; OR, 1:19:1, 38.)  As the day dawned on September 7, the bulk of McClellan's army sat across the Potomac from Virginia.  Little Mac was on the move, and Sigel's men may have started to wonder when their turn would come.

Notes

*This fight likely occurred near the current-day location of the Whole Foods supermarket along Leesburg Pike (Rt. 7)  (See here for a map). 

**Ft. Marcy and Ft. Ethan Allen guarded the immediate approaches to Chain Bridge on the Virginia side of the Potomac above Georgetown.  For more on the two forts, see here and here.  Ft. DeKalb sat near current-day US-29 (Lee Highway) between N. Adams and N. Vance Streets in Arlington, Virginia.  It was later renamed Ft. Strong.  Hunting Creek is a tributary stream of the Potomac located to the south of Alexandria, Virginia near the present-day Woodrow Wilson Bridge.   Ft. Lyon was located beyond Hunting Creek to the southwest of Alexandria.  For a complete map of the defenses of Washington from the OR, see here.

Sources

Aside from the citations to the Official Records above, the following sources were useful in compiling this post:

Samuel P. Bates, History of Pennsylvania Volunteers, 1861-1865, Vol. I (1869); Benjamin Franklin Cooling III & Walton H. Owen II, Mr. Lincoln's Forts: A Guide to the Civil War Defenses of Washington (2010 ed.); Stephen D. Engle, Yankee Dutchman: The Life of Franz Sigel (1993); Bradley Gottfried, The Maps of Antietam (2012); Joseph L. Harsh, Taken at the Flood: Robert E. Lee & Confederate Strategy in the Maryland Campaign of 1862 (1999); George Michael Neese, Three Years in the Confederate Horse Artillery (1911); Stephen W. Sears, Landscape Turned Red: The Battle of Antietam (1983).