Zachariah Clapp (Clump), Loyalist Farmer of Westchester, April 1777

In April 1777 Patriot authorities in New York uncovered a plot by Westchester farmer Zachariah Clapp (often spelled Clump) to slip across the lines to the British. Clapp was known locally for his Loyalist sympathies and brazen defiance of American controls. Commission records describe him as a Westchester County farmer who freely boasted of visiting British-held New York. Two neighbors testified that Clapp bragged “he had been beyond our Lines” and said he would go “to our lines where and when he pleased”[1]. When reined in, Clapp hotly declared it was unfair that “people might not go where they pleased” and insisted that “for his part he intended to go where he chose”[2]. These statements – confirming his intent to carry on unfettered travel between Patriot and British zones – strongly marked him as a Tory collaborator. (In the Commission’s minutes he is repeatedly labeled “Zachariah Clump, alias Clapp.”) Clapp’s own statements and actions, as recorded by witnesses, reveal his allegiance: he was willing to cross into enemy territory even after American forces had designated Westchester a “neutral ground” wedged between the armies[3][1].

Accomplices and Witnesses: Clapp was not acting alone. Two accomplices – Ferdinand Van Sicklen and Thomas Brush – joined him in planning a trip to the British lines. Van Sicklen was also a Westchester militiaman who later repented, while Brush was another local resident. Two other neighbors alerted the patriots: Caleb Mitchell and Joseph Whelpley. On April 17, 1777 Mitchell and Whelpley appeared before the Commission and swore that, just the day before, Clapp had boasted of his crossings. Mitchell’s deposition states:

“Zachariah Clump informed [me]… that he had been beyond our Lines; that when [I] reprehended him for going he replied that he would go [to] our lines where and when he pleased, or words to that effect.”[1]

Similarly, Whelpley testified that Clapp said he had indeed gone past the lines and maintained it was “hard” to forbid people free travel, “and that for his part he intended to go where he chose”[2]. These depositions of Mitchell and Whelpley were sworn and signed (each was cross-checked by a neighbor) and clearly implicate Clapp as an intentional traveler to the enemy.

Meanwhile, Van Sicklen’s deposition (taken April 25) admitted that he, Clapp, and Brush had set out with “a determination to go to the Enemy” by crossing through the American lines[4]. Van Sicklen related that on this foray he turned back in conscience – having taken up arms for America and left “a Wife & children behind” – but Clapp and Brush proceeded, only to be later observed retreating as well[4]. Thomas Brush’s sworn statement (April 25) corroborated Van Sicklen: he “admits they set out & returned again in the same manner and for the same reasons mentioned in Van Sicklen’s deposition”[5]. In short, all witnesses agreed that Clapp had indeed tried to penetrate to British-occupied New York and then withdrawn at the last moment.

Clapp’s Movements: The testimony makes clear Clapp’s movements and attitude. He freely told neighbors he had been “beyond our Lines” (i.e. into British-controlled territory)[1]. When rebuked, he flared up that no one should restrict his travel. His companions Van Sicklen and Brush recounted leaving Westchester on Tuesday, April 16, 1777, with Clapp to visit the enemy. Van Sicklen said they had gone “down to our Lines” (across the Hudson to the right bank under British sway)[4]. When Van Sicklen’s conscience prompted him to stop and return at Haviland’s near Pine’s Bridge, Clapp silently continued toward the lines with Brush. En route back, all three passed a Dr. Belden (a known Tory contact) who recognized them[6]. Thus, Clapp fully realized he was traversing the Americans’ vulnerable frontier zone. Even after capturing him, Patriot officials recorded Clapp’s unrepentant attitude: when confronted with the impropriety of his journey, he never denied it, only insisted on his right to move freely.

Patriot Response – Commission for Detecting Conspiracies: The New York Provincial Congress had established the Commission for Detecting and Defeating Conspiracies precisely to handle cases like Clapp’s in the neutral ground. On April 17, 1777, after taking depositions from Mitchell and Whelpley, the Commission ordered Clapp, Van Sicklen, and Brush “to be committed” (taken into custody)[7]. Four days later (April 21) guards brought the trio before the Board of Commissioners. Van Sicklen and Brush were formally examined on April 25. The Commission allowed Van Sicklen and Brush to go at large on parole pending further inquiry. On April 28, the Commission reconvened (Egbert Benson and Melancton Smith presiding) and examined Brush’s deposition, which confirmed the attempted trip[5]. All evidence pointed to Clapp’s guilt as a subversive.

Evidence and Proceedings: The Commission’s records contain the sworn testimonies, which were considered strong evidence of Clapp’s conduct. Key excerpts include: - Caleb Mitchell (neighbor): “Zachariah Clump … had been beyond our Lines… he replied that he would go to our lines where and when he pleased”[1].

• Joseph Whelpley (neighbor): “he told [me] that he had been beyond our Lines… [Clump] said it was hard people might not go where they pleased and that… he intended to go where he chose”[2].
• Ferdinand Van Sicklen: “the Deponent [Van Sicklen], Clump & Brush set out… to go to the Enemy, & went down to our Lines” (to Manhattan), and when Van Sicklen turned back, “Brush observed he would return… but Clump made no reply”[4].
• Thomas Brush: Confirmed he and Clump “set out & returned again in the same manner and for the same reasons mentioned in Van Sicklin’s deposition”[5].

These depositions were signed and filed in the Commission’s books. After review, the Board discharged Van Sicklen and Brush (concluding they had shown remorse)[8]. Clapp himself was brought before the Board later that day and voluntarily took an Oath of Allegiance to New York[9]. The record tersely notes: “Ordered that he be discharged.” No further punishment was recorded beyond the oath. In effect, Clapp was released on parole as a reformed loyal subject (at least on paper).

Strategic Context – Westchester’s Neutral Ground: Clapp’s case must be understood against the backdrop of Westchester County in spring 1777. After the New York campaign of 1776, British forces occupied Manhattan and entrenched camps in southern Westchester (e.g. at Kingsbridge and Yonkers)[3]. Americans held the highlands to the north, leaving the roughly 15×10 mile “neutral ground” in between hotly contested and largely lawless[3]. This zone was plagued by Tory raiders, spies, and guerrillas. Patriot officials like Governor George Clinton struggled to establish civilian order there. Washington and New York’s Committee of Safety realized they needed extraordinary measures. In late 1776 and 1777 the state legislature empowered a special Commission to “send for persons suspected of being enemies” and investigate subversion (as described in the Commission’s mandate)[10][3]. Clapp’s boastful cross-boundary treks exemplified the very kind of threat this Commission was created to counter. Indeed, historian Joshua Canale notes that from 1776 to 1781 New York authorities “extensively monitor[ed] dissent,” using bodies like the Detecting Conspiracies Commission to police travel and deport suspicious residents[11]. Westchester’s precarious position, with divided loyalties in its mixed population, meant counterintelligence vigilance was crucial[3][11].

Impact on the War Effort: The arrest of Clapp highlights how Patriot officials waged an internal intelligence war in New York. Although Clapp escaped severe punishment, the incident served as a warning to other Loyalists in the neutral ground. The Commission’s rapid response – gathering sworn testimony and forcing an oath – demonstrated that neighbors could hold each other accountable. It also underscored the difficulty Washington had warned about: without tight controls, “subversives” like Clapp could exploit open travel to the enemy[11]. By exposing Clapp’s contacts (even eliciting the names of other would-be defectors from Van Sicklen’s testimony), the Commission effectively disrupted this particular conspiracy. More broadly, documenting Clapp’s case helped legitimize the new machinery of surveillance and loyalty oaths in New York. In a theater where ordinary civilians’ allegiance was unpredictable, Clapp’s case made clear that Patriot authorities would use every tool to protect communications and supplies from Tory interference. In the spring of 1777 – as the Continental Army prepared for campaigns and the British probed northward – ensuring Westchester was not a festering rear for spies was vital. The Clapp affair thus reflects the tense counterintelligence climate on New York’s volatile frontier, and it bolstered the Patriot effort by deterring like-minded Tory activities in the region[3][11].

Sources: This report draws on the minutes of the Committee and Commission for Detecting and Defeating Conspiracies (the official records of New York’s wartime executive). All witness depositions and orders are quoted from those minutes[12][9]. Contextual information on Westchester’s status as the Revolutionary “neutral ground” comes from modern histories and National Park Service analyses[3][11].

Bibliography

• Minutes of the Committee and of the First Commission for Detecting and Defeating Conspiracies in the State of New York, December 11, 1776 – September 23, 1778. Collections of the New York Historical Society vol. LVII (Albany: New York Historical Society, 1925). Edited by Dorothy C. Barck.
• National Park Service. “The Revolutionary War ‘Neutral Ground’ of Westchester County, New York.” U.S. National Park Service. Last updated June 30, 2023. https://www.nps.gov/articles/000/the-revolutionary-war-neutral-ground-of-westchester-county-new-york.htm.
• Canale, Joshua. “New York Committee and Council of Safety.” Washington Library Digital Encyclopedia, George Washington’s Mount Vernon. (n.d.) https://www.mountvernon.org/library/digitalhistory/digital-encyclopedia/article/new-york-committee-and-council-of-safety.

[1] [2] [4] [5] [6] [7] [8] [9] [12] Full text of "Minutes of the Committee and of the first Commission for detecting and defeating conspiracies in the state of New York, December 11, 1776-September 23, 1778, with collateral documents : to which is added Minutes of the Council of appointment, state of New York, April 2, 1778-May 3, 1779 .."

https://archive.org/stream/minutesofcommitt571newy/minutesofcommitt571newy_djvu.txt

[3] The Revolutionary War "Neutral Ground" of Westchester County, New York (U.S. National Park Service)

https://www.nps.gov/articles/000/the-revolutionary-war-neutral-ground-of-westchester-county-new-york.htm?utm_source=article&utm_medium=website&utm_campaign=experience_more&utm_content=large

[10] [11] New York Committee and Council of Safety | George Washington's Mount Vernon

https://www.mountvernon.org/library/digitalhistory/digital-encyclopedia/article/new-york-committee-and-council-of-safety