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Brigadier General Henry Knox’s Artillery Estimate for 1778, 10 November 1777

Brigadier General Henry Knox’s Artillery Estimate for 1778

Artillery Park [Whitemarsh, Pa.] 10th Nov. 1777

Estimate of Ordnance, Arms, and Stores necessary for the Army of the United States for the Campaign of the year 1778, supposing it to consist of Forty thousand Men.

Battering Train of Cannon, Mortars, &ca

Iron Cannon 30 18 Pounders } On Travelling Carriages—6 spare ones for the 12 Prs and 6 for the 18 Prs
30 12 Do
Iron Mortars 12 13 Inch. } With Beds Complete—3 spare beds to the 13, and 5 to the 10 Inch
20 10 Inch.

Provided the Iron be good of which the above Cannon and Mortars shall be made they will answer as well as Brass. The difference of weight between Brass and Iron in Battering Cannon and Mortars of the above calibres would be but triffling.

Iron Battering Cannon and Mortars may be cast at Salisbury Furnace near Hudson’s river, and at Mr Zain’s Furnace in Virginia, at both of which places the Metal is excellent. The Carriages can be made at Springfield and at Carlisle by the Continental Artificers.

There are at Boston seven fine 18 Pounders ready mounted, and three 13 inch Sea-Mortars. These were sent by Congress to the State of Massachusetts’ Bay when the Enemy evacuated Boston. The Cannon were brought from Ticonderoga, and the Mortars were left by the Enemy.

Brass Mortars 20 8 Inch. } Complete with Beds—5 spare for the 8 inch, and 7 for the 5½.
30 5½.
For the Field, or Battering, occasionally.
10 Howitzers 10 Inch. } On Travelling Carriages
20 Do 8. 2 spare to the 10 inch.
30 Do 5½. 3 do to the 8.
6 do to the 5½.
Field Artillery:
Brass 12 24 Pounders } On Travelling Carriages
24 12. 3 spare to the 24 Prs
150 6. 6 do to the 12.
150 3. 20 do to the 6 Prs &
20 do to the 3 Prs

We have as by the annexed Return, 170 Field Pieces, and 21 Mortars.1

The Copper Mines at Middlebrook in the Jersies may be easily worked. Mr Vanhorne will engage, if the Continent will furnish him with one hundred men, to turn out 150 Tons of Copper a year. We have several Cannon cast of Copper which came from this place. It is a matter of so great importance, that too much attention cannot be paid to it.2

The Furnaces at Springfield and Carlisle, when finished, would in two or three months cast a number of Cannon sufficient to make up the dificiency.

Shot and Shells
5000 24 Pound Shot
30000 18.
30000 12.
60000  6.
30000  4.
60000  3.
1000 Tons Grape Shot of various sizes from one ounce to one pound Balls.
6000 13 Inch Shells
10000 10.
12000  8.
20000  5½.

These Shot & Shells may be cast at any Furnace.

2000 setts Horse Harness
1000 setts Mens Do
500 Covered Ammunition Waggons.

The Harness and Ammunition Waggons may be made at Springfield and Carlisle.

60000 New Pouches or Cartridge Boxes. The Leather to be well tan’d, to be made with double flaps, and the ends secured by a flap to shed the rain—each to hold 36 rounds. The best new British Model to be procured as a pattern.
60000 Tin Cartridge Boxes (besides the above) each to hold 36 rounds.

These Pouches and Tin Cartridge Boxes can be made at Springfield and Carlisle.

2,000000 Musket Flints.

I know of no method to obtain these, but by importing them.

1500 yards Flannel

may be made by the Country People, or be imported.

200000 Screws to draw Charges

may be either made or imported.

40000 Muskets and Bayonets ought to be in reserve in case of accidents.

It is to be lamented that there have not been established Manufactories of Arms on a large scale. In my opinion a method might be pointed out, and Artificers collected, who would in a great measure supply the Continent with Arms. As this cannot be the case, immediately, it will be necessary to import a number.

3000 Spears, to arm a Body of Infantry

2000 Espontoons, for the Officers

2000 Broad Swords with Belts for the Artillery

These Articles may be made, at the Continental Works.

400 rounds per man for 40000 men, each round containing half an ounce Pounds weight
400 rounds per cannon for 300 Cannon, each round averaged at 4 pounds 480000
For extra services, such as Garrisons, Gallies, &ca 500000
Contingences 500000

This Powder may either be made, imported, or borrowed from the different States.3

400 rounds per man for 40000 men Pounds weight
each round one ounce 1,000000
Contingencies 1,000000

I am informed there are Lead Mines in Virginia; if so, they are well-worthy the attention of the Public. There must be considerable quantities of Lead belonging to each State, which ought to be collected with the utmost expedition.

There will be wanted, besides the abovementioned Articles, large quantities of Timber Iron &ca for the Carriages, Mortar Beds, & Ammunition Waggons. Also a vast variety of small Articles for the composition of Port Fires, Tubes, Fuzes, &ca which will be provided and made by the Directors at the different Laboratories.

H. Knox B. G. Artillery

DS, DNA: RG 93, manuscript file no. 20692. Both the estimate and the enclosed return are in Samuel Shaw’s writing and are endorsed by Knox, “Copy sent to the board of War.” The items are docketed “copy of Estimate of Return of Ordnance Stores delivered by Genl Knox to Board of war—Novr 10th 1777.” However, the internal address on both documents reads “His Excellency George Washington.”

1The enclosed document, dated 10 Nov., reads:

Return of Ordnance belonging to the United States of America

Field Artillery
In the Main Army 2 Brass 12 Pounders
26 Ditto 6.
6 Ditto 4.
6 Do. 3.
4 Do. Howitzers 5½ inch.
1 Do Ditto 8 inch.
With Genl Putnam 1 Brass 24 Pounder.
2 Do 6.
12 Do 4.
2 Do Howitzers 5½ inch.
With the Northern Army
  Sent there 10 Brass 4 Pounders
  Taken from the Enemy 2 Do 24.
6 Do 12.
22 Do 6.
11 Do 3.
2 Do Howitzers 8 inch.
At Charlestown,
  So. Carolina 19 Brass supposed to be 4 Ps.
At Springfield
  Massachusetts 20 Brass 4 Pounders
At Boston 1 Brass 4 Pr
At Allentown, the mounting not yet finished
2 Brass 3 Pounders.
2 Do 4.
3 Do 6.
4 Do Howitzers 5½ inch.
1 Do Do 8 inch.
1 Wrought Iron 3 Pounder.
At Carlisle 2 Do Ditto.
Total 170 Pieces
Ordnance borrowed by the Continent
from Massachusetts 1775 4 Brass 3 Pounders
New York 1776 6 Do 6.
Pennsylvania 1777 2 Do 6.
2 Do 12.
Mortars and Cohorns.
At Springfield 1 Brass Inch.
At Litchfield 2 Brass 8 Inch.
10 Do 5½.
2 Do 4½.
With the Northern Army 2 Brass 10 Inch.
Taken from the Enemy 4 Do 5½.
Total 21.
Battering Ordnance
At Boston 7 Iron 18 Pounders
3 Iron Sea Mortars 13 inch.
Brass Field Artillery 3 24 Prs
8 12.
53 6.
70 4.
22 3.
10 Howitzers 5½ inch.
 4 Ditto 8 inch.
Brass Mortars & Cohorns 2 10 Inch.
2 8.
15 5½.
2 4½.
Iron Cannon 7 18 Pounders.
Iron Sea Mortars 3 13 inch.

The return is in DNA: RG 93.

2Several copper mines in the vicinity of Middlebrook Gap in Bridgewater Township, Somerset County, N.J., were associated with the Van Horne family, including one on a ridge on the southwest flank of the First Watchung Mountain that came to be known as the “American mine” (Weiss and Weiss, Old Copper Mines of New Jersey description begins Harry B. and Grace M. Weiss. The Old Copper Mines of New Jersey. Trenton, 1963. description ends , 30). Philip Van Horne, a colonel of militia during the French and Indian War and a judge of the court of common pleas for Somerset County since 1759, lived at his mansion house, which is still standing, on Phil’s Hill, or Convivial Hill as it also was called, located on a “slight elevation immediately west of Middlebrook, and north of the highway leading from Bound Brook to Somerville” (Bergen, “Phil’s Hill,” description begins James J. Bergen. “‘Phil’s Hill,’ The Home of Colonel Van Horne.” Somerset County Historical Quarterly 1 (1912): 81–85. description ends 81). Van Horne apparently entertained both British and American officers at Phil’s Hill until July 1777, when Col. Theodorick Bland of the Continental light horse set up his headquarters there. Lord Stirling also headquartered at Phil’s Hill during the winter of 1778–79, and American troops occupied the estate throughout the remainder of the war. Van Horne’s eldest daughter, Mary Ricketts, married cavalry officer Stephen Moylan in September 1778.

3Shaw failed to add correctly the weight of the powder. The accurate sum is 1,980,000 pounds.

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