There are facts from which we can ascertain the minimum number of men
 in five of the boats: those bearing Potter, Mawney, Bowen, Brown, and Ormsby.

Number in Potter's boat. Potter's boat was described by informant Arron Briggs, a slave.  Briggs was impressed by the Potter group to aid in the rowing. Briggs describes the situation as "....he was in a boat which was rowing with eight oars"; that the time Potter impressed him into rowing in Potter's boat " . . . Potter was about five miles from Bristol; that there were eleven men in said boat."   That indicates with the eleven men in the boat plus Briggs there were 12 men in Potter's boat.  [Note how this fits the facts. With a "five oared boat", which really means in today's language, "ten single oars", one way to have a boat rowed an 11 mile distance, as Potter was doing coming from Bristol, is to have at least two men rest (leaving eight oars being used) and rotate the resting among the rowers.]

Number in Mawney's boat. Consider the Statement of Dr. John Mawney (see Staples, p15-16). [After hearing the drum beat, he went to Sabin's tavern, where he learned the object of the meeting; and was asked to accompany them, as surgeon.] "To this, I readily consented, and went to Corlis' wharf, with Capt. Joseph Tillinghast, who commanded the barge, it being the last boat that put off     . ..  I was then sitting with Capt. Tillinghast, in the stern of the barge.

Before considering the minimum number in the Tillinghast captained boat, we should note Mawney's reference to "barge".  Providence was a maritime town, with a majority of the males being familiar with ships and the classes of ships and boats.  For sailors in the 1700's a remark about a "barge" would be taken to mean a ship's large used for transportation of large amounts of materials and men to and from ship and shore at the various ports. In New England a "barge" was built to hold more than eight or 10 men.  Consider, for example, that Brown was active in the slave trade, and the "barge" needed for the safety of an armed crew going ashore to bring back slaves to the ship needed to be capable of holding several persons.  When Brown, on the night in question, ordered the assembling of the "largest longboats" available, one could expect longboats that would fit the description of a "barge".

Note English Navy Midshipman Dickinson's reference to the attacking boats as "including launches."  A Midshipman was the lowest rank of officer on a ship (somewhat like our Navy's Ensign) and could be expected to both know and use proper terminology when describing a boat or ship. The English Navy defined a "barge' or a "launch" on a English Navy ship as a large boat, capable of being sloop-rigged, and -- importantly as part of the naval definition -- capable of carrying at least a squad of fully armed men, plus the number of sailors needed to sail or row the barge (also known as a launch) back to the warship.  "Barge"  was the term used by the English navy for the ship's boats intended to land the royal marines to fight.  "Launch" was a broader term, including not only a barge, but also including the ship's boat used for bringing supplies from shore to a large warship or large merchant ship. If an English royal navy midshipman used the term "launch", Navy officers would understand it to mean a a large boat, capable of being sloop-rigged, and capable of carrying more than a dozen men.

Now back to Mayney's statement " ..  I was then sitting with Capt. Tillinghast, in the stern of the barge."  Mawney and Tillinghast were not rowing. The boat was a large boat, not easily handled by a crew of only a half dozen intending to row six miles --- against the tide --- to attack the Gaspee.  The 10 oars must have been completely crewed without the help of Tillinghast or Mawney.  We conclude there were 12 men at least in Capt Tillinghast's longboat.  And still the Tillinghast boat had more room --- the entire Gaspee crew of 20 men (hands bound behind them) was carried off  the Gaspee in only two of the attacking longboats, and Tillinghast's longboat was one of them.  There logically must have been at least a dozen men in the boat carrying Dr. Mawney.

Number in Bowen's boat. Bowen tells in his account of Joseph Bucklin not being in a rowing position as they approached the Gaspee.  Brown had ordered "eight of the largest longboats" available, with  five sets of oars This would indicate at least 12 men in Bowen's boat (the 10 persons rowing plus, at a minimum Bucklin and the captain of the boat). 

Number in Brown's boat. John Brown was not the sort of man to be rowing.  First of all, because of his gentleman station in life, he would not be rowing. Second, according to estimates of the Rhode Island Historical Society based on his clothing, John Brown weighed about 250 pounds. With some confidence we can say he was not rowing the boat the six miles needed for the attack.  That indicates at least 12 men in his boat.

Number in Ormsby's boat.  Ezra Ormsby, in his statement said his boat from Warren had: "Capt John Greenwood, James Smith, Abner Luther, Abel Easterbrooks, Nathaniel Easterbrooks, Hezekiah Kinnicut and myself".   That would be seven men.  Ormsby specifically described his boat as a "whaleboat".  A whaleboat was a particular kind of boat,  usually carrying a crew of five men.  Using a whaleboat to row to Namquid point from Warren would be logical, because of its design for fast and easy rowing in the about 12 mile row to the attack site. However, the small size of the whaleboat and its peculiar oar configuration would only allow the town of Warren to supply Brown's raiding force with a ship captain and six other men.

Thus, in the five longboats of which we have rather firm conservative estimates, there were 55 men.  We do not have firm information on the remaining five longboats, all of which were longboats from Providence, but we can strike a probable average. To extended discussion of how many boats and of the total of men were in the attacking force.