... canter off to the right and left ...
B.J.K. Anderson. Narrative of a Journey to Musarda, the Capital of the Western Mandigoes. 1870
Если не путаю - гвинейские мандинка.
On Monday, the 14th of December, 1868, the King Vomfeedolla held a military demonstration. He had summoned his infantry and cavalry from the nearest towns of Billelah, Yokkadu, Naalah, and Mahommadu. The exercises commenced about two o'clock P.M., in the large square of the town. The spectators and musicians had already assembled. All at once a trooper dashed past at full speed, as if he was reconnoitring the enemy. Several others followed, dispersing in different directions. The position of the enemy seeming to be determined, they soon returned. The trumpet then sounded, and a grand cavalry charge took place. Riding up in line, with musket in hand, they would deliver their fire, and canter off to the right and left, in order to allow the rear lines to do the same. As soon as the firing was over, they slung their muskets, and, rising in the saddle, drew their long knives in one hand and their crooked swords in the other; the horse, now urged to a headlong gallop by the voice, carries his rider, standing in the stirrups, with furious velocity into the heat of the battle. Such are the evolutions of the Mandingo cavalry. Their equipment is quite complete. They use saddles and bridles, and a peculiar and powerful bit; short stirrups; leather leggings, to which iron spurs are attached. The cavalry from all the towns, according to various reports, ought to amount to fifteen hundred.
In their open country, where the action of cavalry is greatly facilitated by the long, gentle slopes, and wide, treeless plains, they would be no mean enemy. They often dismount, in order to act on foot. Each horse has a boy attendant to take care of him while his master is thus engaged. In real action, I have been informed, the little boys of the defeated party often suffer the penalty of their participation. Yet these dangers do not deter the little fellows from going; for they are frequently able to ride off the field as soon as any symptoms of defeat are perceived.
The king seems to act for the most part with the infantry, for he rode in front and led them on. They came in deep array, and with great clamor, but without organization, being directed solely by a flag or ensign of blue cloth. I was sorry that I had no flag of ours to present them.
After their exercises were over, they requested us to fire our muskets; upon which we delivered regular volleys with bayonets fixed, both to their astonishment and delight, caused by the quickness with which we loaded our pieces, our certainty of fire - unlike their fusees, which were continually snapping - and the deeper report of our guns. As soon as all the exercises were finished, the king then distributed the presents I had given him to the chiefs of the several military divisions.
Для сравнения - тут, тут, тут и тут.
Robert Ward. Animadversions of warre. 1639
Note the Harpuebuziers are to give fire by rankes; the first ranke having given fire, is to wheele off to the left hand (unlesse the ground will not permit it, (but that of necessity you must performe it to the right) making ready and falling into the Reare: the second ranke is to give fire upon the wheeling away of the first, and so the rest successively.
Иллюстрация из Johann Jacob von Wallhausen. Kriegskunst zu Pferdt. 1616
Jackson J.G. An Account of the Empire of Marocco, and the Districts of Suse and Tafifelt. Compiled from Miscellaneous Observations Made During a Long Residence In, and Various Journies Through, These Countries. 1809
... their exercise of cavalry consists in what they call El Harka, which is running full speed, about a quarter of a mile or less, till they come to a wall, when the rider fires his musquet, and stops his horse short, turning him at the same time; this amusement, of which they are ridicoulously fond, they continue several hours, wasting much powder to little purpose, as they do not improve in the direction of their piece, having no ball with the charge, nor mark to fire at; their pieces have nothing in them but gunpowder rammed down, for if they had wadding, many accidents would happen from their discharging them close to one anothers faces. Ten or twenty horsemen suddenly dart off at full speed, one half turning to the right, and the other half to the left, after firing, so as not to interfere with each other.
Краткое положение с нужнейшими объявлении при учении (конного) драгунского строю. Или тут, в Строевые уставы и наставления русской армии XVIII века. Т.1. 2010
А егда первая шеренга выпалит, тогда направо и налево выступать спешно, и выступая, заряжать ружье, и приехав, стать назади, где стояла задняя шеренга, и приехав, тотчас поднять мушкет на караул, а вторая выступает на первые шеренги место. По тому же и прочие шеренги.