One of the first steps taken by the Governor, General Eliott, was to attach 180 men from the infantry to the Artillery, to learn gunnery, and assist in the duties of the latter. The regiments in garrison were the 12th, 39th, 56th, and 58th, also the (then) 72nd regiment. The (then) 73rd and 97th regiments joined during the siege. There were also 124 Engineers and artificers, and three regiments of Hanoverian troops. The total strength of all ranks in June 1779, was 5382; but it increased before the siege was over—by means of reinforcements from England—to 7000.
A few statistics connected with the Artillery and their duties may, perhaps, with advantage be prefaced to the account of the siege.
The amount of ammunition expended between September 1779|and February 1783, was as follows:
| Shot | 57,163 |
| Shell | 129,151 |
| Grape | 12,681 |
| Carcasses | 926 |
| Light Balls | 679 |
In all 200,600 rounds, and 8000 barrels of powder.
The preponderance of the number of shell over shot was caused by the use, during the siege, of shell from guns, with reduced charges—as well as from mortars and howitzers; suggested by Captain Mercier, of the 39th Regiment, and found so successful, as almost to abolish the use of shot during the first two years. In the year 1782, however, the value of red-hot shot against the enemy's fleet and works was discovered; the amount of shot expended rapidly increased; and while there was hardly a battery without the means at hand for heating them, there was also a constant supply, already heated, in the chief batteries.
The batteries from which the Artillery generally fired on the land side were those known collectively as Willis's; but when the fleet, and especially the hornet-like gunboats, commenced annoying the garrison, the batteries towards the sea had also to be manned, and the duty became so severe, that at times the fire had to be slackened, literally to allow the men to snatch a few hours' sleep.
The proportion in the Royal Artillery of killed and wounded was very great. According to the records of the 2nd Battalion, the list was even heavier than that given by Drinkwater in his celebrated work; but even accepting the latter version as correct, it stood as follows:—
Out of a total of 485 of all ranks, there were:—
| Killed | 23 |
| Died of wounds | 8 |
| Totally disabled | 13 |
| Wounded | 116 |
| Died of sickness | 36 |
| ——— | |
| Total number of casualties | 196 |