LAFAYETTE SENT TO VIRGINIA
Washington sent the Marquis de Lafayette to Virginia in April 1781 with a force, including some of the sappers and miners, to stop Arnold’s raids. The chief engineer was a valuable asset because Washington valued Duportail’s knowledge of the enemy position in New York, his proven ability to evaluate the rebels’ strength, and his camaraderie with fellow French officers like Rochambeau.11
Washington’s headquarters, New Windsor, New York. Photo courtesy of the author.
Duportail set out for New Windsor on the Hudson after taking leave of the Comte de Rochambeau and the officers of his army. He arrived on April 6, and General Washington wrote to General Lafayette two days later, countermanding the permission he had given Lafayette to increase his staff by the addition of Lieutenant Colonel Gouvion: “It is General du portail’s desire that Col. Gouvion may return to him. Independant of the occasion which there may be for him here, there is another reason which operates against his going with you; it is that he would interfere with Col. Kosciusko who has been considered as the commanding engineer with the southern army.”12 Moreover, Kosciusko never wanted to serve under the French commandant of the Corps of Engineers.
The Marquis replied on April 13 that he would have liked to keep Colonel Gouvion, and he forwarded Washington’s orders to Philadelphia, where Colonel Gouvion was located. Meanwhile, Washington wrote to the Comte de Rochambeau on April 7,
As genl. du portail did not arrive till yesterday, I had no opportunity of conversing with him before this day. After relating to me what has passed between your Excellency and himself, and being informed by me of the resolution I had taken to let your troops remain at Newport for the present and with the reason which induced me to take that resolution, he fully acquiesced with me in the propriety of it.13
Washington received a letter from the Comte de Barras on May 11, announcing his safe arrival at Newport to command the fleet of the Chevalier Destouches, who assumed command after the death of Admiral Ternay. Washington immediately replied, congratulating him and announcing the date of the interview that was to take place between the French and American commanders on May 21 at Wethersfield, Connecticut.
WETHERSFIELD MEETING
The Comte de Barras’s flagship, Concorde, also brought the Vicomte de Rochambeau with the latest instructions from the Court of France. Duportail accompanied Washington at the historic Wethersfield meeting and was present at all the discussions. They returned to New Windsor on the twenty-fourth, and the French delegation went back to Newport. The Concorde was then dispatched to the Comte de Grasse in the West Indies with the report of the deliberations held at Wethersfield.
A letter from Colonel Laurens in Paris informed Washington on the twenty-sixth that the king had announced the free gift of six million livres to the United States. Two days after receiving Colonel Laurens’s letter, Washington wrote to General Duportail,
You are perfectly acquainted with the plan, which has been concerted with his Excellency Count de Rochambeau at Wethersfield, I need not enter into a detail of particulars. I have only to request, therefore, that you will be pleased to make the estimates of the articles in your department necessary for the operation and that the previous arrangements for the siege as far as they are within the limits of our ability, be put in the best train, which the circumstances will admit. In the mean time, it has become necessary, from decay of the works . . . to abandon the post of Fort Schuyler, and erect new fortifications, at or near Fort Herkimer; I have to request that you will send an engineer to superintend the works in that department.14
PREPARATIONS FOR AN ATTACK ON NEW YORK
General Duportail sent Major Villefranche to superintend the erection of any defenses as would be necessary at Fort Herkimer and vicinity. He then turned his attention to preparing for an attack on New York, as tentatively determined at Wethersfield.
Washington instructed Duportail on May 28 to estimate the engineering department’s needs for conducting a siege. The chief engineer responded in a matter of days. His evaluation included a rare calculation of the manpower and time required to make some of the principal instruments of siege craft: gabions, saucissons, and fascines:
DUPORTAIL’S ESTIMATE OF REQUIREMENTS FOR A NEW YORK SIEGE
New Windsor, June 2, 1781
Gabions and fascines. Gabions are the basket-like objects in the background. Fascines are the bundles of sticks in the foreground. Together, they are used to strengthen the walls of earthworks and fortifications. Photo courtesy of the author.
Plancks for platteformes about 12 inches broad and 2 inches thick.
I make amount to 150 the number of Cannons of different Caliber and mortars which we Can get and which are necessary whether to batter the ennemy’s lines on new york island or long island or to secure the Communications and some other things.
We must observe that the French army must be provided by us with the following articles.
Each piece Requires about 200 feet of plancks; for 150—30,000 feet. Saucissons (large fascines) for the batteries—72,000 feet. Gabions for batteries or trenches—4000 gabions. Fascines for the same—10,000 fascines.
The proportions of these things will be given to the officer appointed to superintend their Construction.
A man Can make a gabion in one day, so 500 men will make the 4000 gabions in 8 days.
A man Can make 36 feet of saucisson in one day, so 500 men will make the number Required in 3 days.
500 men will make the 10,000 fascines in 6 days.
Sand bags—30,000. We shall probably want some more but I have been told the French army have 60 thousand.
Tools: Shovels—5000; Pick axes—2500; Axes—1200; Bill hooks—800. If the french army had no[t] enough for them, we must have more than it is Required here.15
The sappers and miners were busy making fascines and gabions and frequently helped the engineers with reconnaissance. Washington moved the main body of his army from New Windsor between June 21 and 24. They moved farther down the Hudson and established headquarters at Peekskill on the other side of the river. Dr. James Thatcher, in his Military Journal of the American Revolution, says on June 23, “The army is now concentrated to a point in this place [Peekskill] and encamped in two lines, and in the same regular order that the troops usually form in a line of battle. . . . The campaign is now about to be opened, and we expect in a few days that the French Army will form a junction with us to cooperate with our troops.”16
The two armies joined at Phillipsburg on July 6, still farther down the river and nearer New York. Washington, in his Orderly Book for this date, took occasion to thank “his Excellency the Count de Rochambeau, for the unremitting zeal with which he has prosecuted his march, in order to form the long wished for junction between the French and American forces . . . and from which the happiest consequences are to be expected.”17
COMBINED OPERATION AT NEW YORK
A few days before, a combined operation had taken place against the Crown forces when the Duke de Lauzun brought his own legion to support a detachment under General Lincoln, who had dropped down the Hudson at night and taken possession of ground a few miles back of Kings-bridge. As a result, the Crown forces retired to the other side of the Harlem River and took up their position behind Fort Washington on New York Island (Manhattan). In a letter to the president of Congress written the same day but before the arrival of Rochambeau and his army, Washington says of the retirement, “This afforded General Duportail and myself the most favorable opportunity of perfectly reconnoitering the works upon the north end of the island, and of making observations which may be of very great advantage in the future.”18
The commandant of the engineers immediately put these observations to practical use. He began making a plan of attack to put into operation as soon as positive news arrived regarding the movements of Grasse and his fleet. The general officers assumed that the attack on New York would still be the wisest move. The combined armies continued to hold p
ossession of the approaches to the north of the island of New York while awaiting news of Grasse and his fleet. The French command had always preferred a united effort in the region of the Chesapeake, however, but they had positive instructions to not influence Washington’s decision in any way or to withstand his wishes.19 Washington’s and Duportail’s preference centered around New York as the place for the first attack, especially after General Clinton had begun sending reinforcements to Lord Cornwallis in Virginia.
The reinforcements stopped during June, and the allies had no way of knowing what the Crown forces intended. Judging by Cornwallis’s position, they thought that his army was to be transported to New York as soon as possible. While awaiting news from Grasse, the commander of the French fleet at Newport, Barras, wanted positive information regarding Washington’s intentions, so he wrote the Comte de Rochambeau, who in turn addressed a letter to General Washington, asking for an interview the next day. In the letter, the Comte says, “I will bring with me the Chevalier de Chatellux and if Your Excellency will kindly advise M. Duportail so he may serve us respectively as interpreter and as approving of what your Excellency judges proper to propose to M. de Grasse under all supposable circumstances.”20
The meeting occurred as proposed by the Comte de Rochambeau, and Washington’s written reply on July 19 to the questionnaire presented to him ends with the following summary:
Finally, every thing considered, I do not see that we can do more than follow the plan decided on at Wethersfield and recommend to the Comte de Grasse to come at once to Sandy-Hook and take immediate possession if possible, of the post of New York and afterwards according to the circumstances which arise to form a definitive plan of campaign based on appearances which seem to appear the most sure.21
Washington sent the following note to the Comte de Rochambeau a few days later (July 25) to be communicated to the Comte de Barras at Newport:
The officer by which I sent my dispatch for Count de Grasse has returned from Monmouth and has brought me an answer from General Forman. . . . the following is an extract from that Gentleman, which your Excellency will be pleased to communicate to Count de Barras, if you think proper.
Saturday the 21st of this month Adml. Graves with six or seven ships of the line sailed from his station off Sandy Hook, the wind at South West—the Fleet steered about South East—their destination not known, but conjectured to convoy Lord Cornwallis from Chesapeake to New York.
General Forman confirms the account of the Royal Oak having gone to Halifax to refit and adds that it is thought she will not be in condition for sea this season.22
The allies could not know the destination of the British fleet under Graves at that time, but today it is possible to know what happened. A sloop arrived at Sandy Hook the day of the meeting between Rochambeau and General Washington. It bore the very important news that Colonel John Laurens would sail from France with “money, clothing and military stores”23 before the end of June. He would be in a convoy of merchantmen escorted by “one ship of the line, another armed en flute and two frigates.”24 The British Admiralty deemed it so important to seize these vessels that it issued orders to the commander of the fleet in the North to that effect. When Graves was seen setting off from his station at Sandy Hook on Saturday, July 21, he was complying with those orders. Dense fog forced him to return to Sandy Hook, where he arrived on August 18. Colonel Laurens came safely into the port of Boston with his precious cargo on the twenty-fifth. The fogs that saved him from the British delayed him so much that the passage required eighty-five days.25
This movement of the largest British ships under Graves, leaving New York harbor comparatively unprotected, seems to have perplexed Dupor-tail, who wrote the following to Washington on July 27:
I am so much vexed since three days ago by a certain idea that I cannot but submit it to Your Excellency. I remember that in the last Conference Count de Rochambeau told that the Count de Barras and all the officers pretended that it was not possible to force the entrance to the harbour of New York when there are some ships to defend it—if so why would not Admiral Barras, in this absence of the British fleet render himself master of the harbour? He could render himself master, he could penetrate every where.
I am surprised that the British left so the harbour and this makes me believe that there is something in their plan which we do not penetrate—maybe a junction with Rodney somewhere. But if the harbour cannot be fired Admiral Graves should not be in danger in it.26
General Washington replied immediately, “The subject you have written upon is equally perplexing and incomprehensible to my understanding—I will talk more freely to you thereon when we meet at two o’clock.”27
DUPORTAIL’S PLAN TO ATTACK NEW YORK
There is nothing in Washington’s papers to throw further light upon the subject discussed at the two o’clock meeting, but Duportail was preparing his plan in the meantime to be ready if and when the moment came to attack New York. He wrote on July 27,
General observations on the manner to pass over the island of New York.
If one considers the nature of the ground in the northern part of the island of New York it will be recognized I think, that it will not be a very difficult thing to take a position on the other side of devil’s creek [Spuyten Duyvil]; batteries can be established on the mountain on that side strong enough to soon force the enemy to abandon Fort Charles and after that we will be masters of Kingsbridge. The works on Cox hill are of small account by themselves and can easily be taken sword in hand. If however the enemy were to remain, after the evacuation or the taking of Fort Charles, which I do not think likely, the feeble state in which they leave the fort on Cox hill shows they do not intend to defend that part of the island, and that their veritable defense front is from Laurel hill to fort Tryon.
Let us suppose that we are masters of Kingsbridge and have taken post on the other side, let us now see how we can progress. Considering the slope of the ground beyond forts Laurel hill and Tryon, its rocky nature, and the position between themselves . . . I do not think it practicable to attack them. . . . Doubtless, going at it properly it might succeed but it is hazardous, so I would prefer the following manner to establish ourselves—which is to go by boats across the Harlem river and boldly take a position between New York and Fort Washington at a place impossible to determine before arriving on the island.
. . . Two things must be considered—whether we will have a French fleet in the Sound, or whether we will not. In the first place we need not fear to be troubled in the Harlem by vessels, galleys or armed boats of the enemy; we will have a much greater number of boats to transport our men; we can choose the place of debarcation upon a very much wider extent of ground; we will have fewer troops to oppose us because the enemy will not be able to spare those on Long Island or even at New York. Success therefore seems to me very probable—it is much less so assuredly in the second case—that of not having a french fleet in the sound but it does not seem to me impossible even then, if we have many troops and much time.28
Duportail then discusses at length the possibilities in case of an attack without the support of the French fleet. He arrives at his conclusion: If a large number of boats can be brought secretly over land for the transportation of the troops over the Harlem River, and if they can command a force at least double that of the enemy, the taking of the island might be successfully attempted.
Duportail finished laying out the final plan for taking New York on July 27. He relied on support from the French fleet, but he deemed it possible to succeed without the fleet “if we have many troops and much time.”29 He thought that 20,000 men would suffice. This document is in the Washington Papers in French and does not appear to have been translated. Apparently, it was sent to Washington on the fifteenth with the following note:
Dear general
i send to your Excellency according to your orders the few general observations i have done after our reconnoiter of the island of New York, although th
e news we had yesterday made me afraid that they are now inutile. your other plans must probably be done but is it not advantageous to pursue the preparations for the attack of New yourk, to deceive our army et so the enemy—i am much afraid that we shall do nothing at all this campagne for want of secrecy—if the enemy perceive that we give up the idea of attacking New york they will reinforce portmouth Virginia, may be before we can get there.30
THE ARMY MOVES SOUTH
Before going south, Washington left Major General William Heath in the New York area to feign further siege preparations and to protect West Point. He then had his men march through New Jersey as if heading for Long Island. The sappers and miners stopped in Philadelphia for several days, “proving and packing off shells, shot, and other military stores.”31 They received shirts, overalls, and stockings, and each got a month’s pay in specie. Sergeant Joseph Plumb Martin recalled the men’s amazement: “This was the first that could be called money, which we had received as wages since the year ’76, or that we ever did receive till the close of the war, or indeed, ever after, as wages.”32
Washington wrote to Lafayette on August 14 with the news that had reached headquarters:
The Concorde frigate has arrived at Newport from Count de Grasse. He was to leave St. Domingo the 3d. of this month, with a fleet of between twenty five and twenty-nine sail of the line, and a considerable body of land forces. His destination is immediately the Chesapeake; so he will either be there by the time this reaches you, or you may look for him every moment.33
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