Original sentence: A curious feature of the British casualty list is that the 1st Battalion, 1st (Royal Scots) Regiment was officially a Scottish unit: yet out of the 41 enlisted men of the battalion who were killed at Chippawa, 22 were Irish, 10 were English, one had "the Army" as his assigned nationality and only 8 were Scottish.The British infantry, with the 1st Battalion of the 1st (Royal Scots) Regiment of Foot and the 100th Foot leading and the 1st Battalion of the 8th (King's) Foot in reserve, were advancing very awkwardly and becoming bunched and disordered, because Riall had formed them into line for an advance over uneven ground with some very long grass instead of keeping them in column, in which they could have advanced more rapidly
Edited sentence: A curious feature of the British casualty list is that the 1st Battalion, 1st (Royal Scots) Regiment was officially a Scottish unit, yet out of the 41 enlisted men of the battalion who were killed at Chippawa, 22 were Irish, 10 were English, one had "the Army" as his nationality and only 8 were Scottish.The British infantry, with the  1/1st (Royal Scots) Foot and the 100th Foot leading and the 1/8th (King's) Foot in reserve, were advancing very awkwardly and becoming bunched and disordered, because Riall had formed them into line for an advance over uneven ground with some very long grass instead of keeping them in column, in which they could have advanced more rapidly