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Robert Treat Paine Papers, Volume 3

From Henry Knox
Knox, Henry RTP
Dear Sir, New York June 24 1776

I receiv’d yours of the 20th instant last Saturday after the post was gone or I should have answer’d it immediately. You desire me to send you the weight and bore of the Iron Howitzers we have here. We have none. Colo. Gridley1 had two cast but they were never us’d. Iron Howitzers are so unweildy from their weight that they are entirely exploded in the British Army. A ten Inch will weigh, 8 Inch 1500, & 52 1000, whereas a Brass 8 Inch Howitzer will not weigh more than 450 or 500, 52 Inch 280 or 300

Their Dimensions
8 Inch 5 1/2 Inch
Inches Inches
length of Chamber 8 Length Chamber 66/10
Diameter ditto 4 Diameter ditto 28/10
from the Chamber to the muzzle—the whole length of the bore 24 from the Chamber to the Muzzle or the length of the bore. 16 5/10

The ten Inch Howitzers have such great re-action that will break any field Carriage whatever therefore they are laid aside. 8 Inch and 5 1/2 to fire at Ships or to fire case shot in the field are some of the best peices of Artillery now us’d. At the air Furnace in this city we have cast four 5 1/2 brass Howitzers as good as those cast at Woolwich, and in the course of this week we shall cast as many more. I have prov’d them and find they will, elevated to an angle of 25 degrees, project a Shell a mile and 45 degrees 1 mile and 1/2. The carriages on which these are to be mounted are not yet finish’d which has prevented my making more accurate Experiments, on a point blank range or at small elevations. I have no doubt that we should be able with certainty to drive a shell thro’ the side of a ship at the distance of six or seven hundred yards, with an 8 Inch 1000 yards. In your Letter of the 20th June you say we cant get Brass. Mr. Byers2 a founder in this city tells me that he has no doubt but in a little time he could procure Copper enough to cast 80 or 100 six pounders each of which will weigh double the 5 1/2 Howitzers. There is a large quantity of Copper at Boston, which could be appropriated to no better use than to be cast into Cannon. There is a Copper mine in the Jersies which might be work’d on this occasion. There are a great number of Stills which are only a pest to society which ought to change their form.

If possible all our field Artillery small mortars & Howitzers should be brass, our heavy mortars and Cannon, Iron. It pleases me much to hear that you cast good 18 pounders &c. at Philadelphia. The buisness of casting Cannon and making fire arms is of infinite importance to this Continent and cannot be too much encourag’d. The 24 pounders at this place are too heavy, they weigh 51.0.0. I have seen some very fine 24 pounders belonging to Rhode Island which weigh’d 40.0.0, which is light enough for so large a Cannon. We have a considerable number of 32 pounders which weigh about 50.51.52 hundred each. The air furnace in this City also one at Newark in the Jersies about nine miles distance are in good order and I make no doubt will be able to cast you any number of field peices either brass or Iron. If there is anything further in this way in which I can be of any service I shall with pleasure do it. You will ’ere this hear of the hellish plot at this place in Consequence of some of the amiable Kings money liberaly distributed here, and also of the spirited Conduct of our friends at Boston in driving away some of the Kings ships, but not perhaps of two more Highland transports which were taken there last monday which is as follows communicated to me by a Letter dated Boston Monday 11 o Clock, June 17


Yesterday were seen in the Bay two large transport vessells suppos’d to be such in an engagement with two or three privateers which they beat off and ran in to nantasket road. Immediately upon their dropping anchor our Batteries from the surrounding posts lately taken possession off began to pray on them on which they put out for sea but were met by a Connecticut Brig Capt. Harden with 14 Carrige Guns 140 hands who after a smart engagement took ’em both. They prov’d to be a Brig and Ship from Scotland with 210 highlanders on board. The Brig mounted a number of 4 pounders the Ship 66 pounders. The Ship had 8 privates and a Major Kill’d a number wounded. Colo. Campbell is among the prisoners.3

This makes five sail of Vessells with highlanders that have been taken.4 I think they open the Campaign badly. I am Dear Sir with Respect Your Most Obt. Hble. Servt.

Henry Knox

RC ; addressed: “Robert Treat Paine Esq.”; endorsed.


Richard Gridley (1711–1796), military engineer, served as lieutenant colonel of the artillery train in the expedition against Louisburg in 1745 and after the death of the chief bombadier took over that function. In the 1750s Gridley was in charge of building or upgrading fortifications in Boston Harbor. In 1770, with two others, he purchased Stoughtonham Furnace, but they were unsuccessful in fulfilling an order for 40 howitzers for the Continental Congress in 1777 and sold the furnace later that year ( ANB ).


James Byers, a brass founder located on Bayard Street, New York City, advertised his wares in New-York Gazette, Dec. 13, 1762 (Gottesman, Arts and Crafts in New York, 194). He later contracted to cast brass cannon for the Continental Congress and established an air furnace for that purpose. See Henry Knox to RTP, July 3, 1776 (below) et seq. A description of his foundery and air furnace appears in John Adams to Charles Adams, Mar. 30, 1777, in Adams Family Correspondence , 2:190.


Henry Jackson to Henry Knox, June 11, 1776 (Knox Papers, microfilm copy at MHS).


The 71st Regiment of Highlanders, raised to reinforce General Howe’s army in Boston, sailed from Greenock, Scotland, Apr. 29, 1776, in 33 transports. A storm scattered the convoy on May 5, and the Americans captured five of the ships (George, Annabella, Oxford, Crawford, and Ann). Archibald Campbell of Inverneill (1739–1791), lieutenant colonel of the Second Battalion of the 71st Regiment, remained as a prisoner in Massachusetts until he was exchanged for Ethan Allen on May 6, 1778. Campbell continued with the British Army in America, was in command at the capture of Savannah on Dec. 29, and then returned to England in March 1779. Later in his career Campbell served as a member of Parliament and, successively, as governor of Jamaica and of Madras (Colin Campbell, “The 71st Highlanders in Massachusetts, 1776–1780,” NEHGR 112[1958]: 200–213 et seq.).