Complex sentence: Methuen ordered all available artillery to provide support fire with the howitzers engaging at and the three field batteries at a range of, while the Horse Artillery advanced to the southern flank in an attempt to enfilade the trenches.
Split into simpler sentences: Methuen ordered all available artillery to provide support fire; the howitzers engaged at and the three field batteries at a range of. The Horse Artillery advanced to the southern flank in an attempt to enfilade the trenches.