Very interesting that the Congreve rocket is shown with the 'ladder' launcher.
The method of launch used by O Battery (The Rocket Troop) Royal Horse Artillery at Leipzig is accepted as :-
The simplest was the launching device use by the mounted men of the Royal Horse Artillery, the smaller rockets were launched along the ground and for this purpose one man in three carried a small iron trough called a ' Bouche a feu'. Congreve described it as a small iron plate trough 18 inches (45 cm) long with four prongs at the bottom to heel it into the ground; it weighed about six pounds (2.72kg) ( The width must have been about 4.5 inches (11.43cm), the diameter of a 6-pr rocket) It was carried in a small leather case, strapped to the rear of the saddle above the valise.
To have a chance of success, the battery’s 28 rocket tubes had to be deployed around 300 yards from the enemy position, and the British came under heavy fire themselves.
“Congreve’s formidable weapon.. accomplished the point of paralysing a solid square of infantry, which after one fire delivered themselves up (as if panick struck).”
Much of the impact was said to have been extraordinary noise of the novelty weapons as well as the fact that its flight, from the moment of ignition, to its explosion in the enemy lines, was visible – unlike traditional artillery of the era. Napoleon’s men fell into retreat and chaos. Up to 3,000 men surrendered to the battery.
For a battery of 145 men that's not bad going.
Additional.
During the Eve of Battle Dinner (17 October) the Battery toasts "the King" [of Sweden] with akvavit and on the anniversary of the battle the reigning monarch of Sweden sends greetings to the battery.