Lord Percy had most judiciously been detached from Boston very early in the morning of the 19th, with a reinforcement of sixteen Companies, and a body of Marines. This force arrived at Lexington just in time to afford a respite to Colonel Smith's detachment, now much harassed by fatigue, and overpowered by very superior numbers.
Having two field pieces, they kept the rebels in awe, until the British resumed their march towards Boston. Major Pitcairne's horse was twice wounded very severely, and he made some narrow escapes during these tumultuous attacks.
Lord Percy, who had advanced to Lexington, by the way of Cambridge, with a penetration and foresight that reflected high honour upon his military talents, determined upon returning to Boston by a different route. The numerous hordes of Americans who had collected on the expected line of his retrograde march, were by this foiled in their hopes of blood, as his Lordship most judiciously turned off towards Charlestown, where he was not looked for, and gained the heights of Bunker's Hill, whither they durst not follow him. To this happy manœuvre the whole detachment owed its salvation, and Boston also may acknowledge his Lordship as its preserver at that early and important crisis.
Throughout the whole of this toilsome service, our loss was by no means equal to the seeming dangers, being only 65 killed, 2 Lieutenants and 20 men taken prisoners, and Colonel Smith, besides some other Officers, and about 174 wounded. Thus was the fatal torch lighted, and it never was extinguished but with American independence.
The whole Country was now roused to arms, and General Gage, with his little army, became invested, within the works of Boston.
Earl Sandwich, who presided at the Board of Admiralty, sensible of the high state of discipline, to which the corps of Marines had reached, pushed them early into the American War. Their conduct upon every duty, reflected credit upon his Lordship's discernment.
In addition to those under Major Pitcairne, who were attached to Lord Percy's Brigade, a farther reinforcement arrived at Boston in the month of May, commanded by Major Short.
It is a tribute justly due to those Officers who so very gallantly supported their Country's honor, and their own, to detail their names, and battalions, agreeably to the arrangement issued in public orders, at Boston, upon the 20th of May.
Battalion orders,
"The Right Honourable the Lords Commissioners of the Admiralty having directed a reinforcement of Marines to serve under Major Pitcairne, in General Gage's Army, consisting of the following number: 2 Majors, 10 Captains, 27 Subalterns, 2 Adjutants, 1 Surgeon, 2 Surgeon's Mates, 28 Serjeants, 25 Corporals, 20 Drummers, 600 Privates.