Друзья, полного перевода, конечно, не прошу - тут все ясно. Есть несколько вопросов по смыслу.

I took with me a young fellow who had joined the Command only a few days. When we galloped up to the struggling team and began to untangle them we were fired upon by
a lot of infantrymen hidden behind a stone fence. When the rain of bullets flattened against the metal forge it sounded as if there were a thousand of them and my young companion, this being his first engagement, toppled over in the road in a dead faint. It was no time just then to look after a sick man, for our horses were frantic with fear and excitement, and I had to hold both of them when the boy fell. I let him lie where he was and in time got my team untangled and tied securely; I was just ready to lead them out, when, very opportunely, my youngster revived. Getting up in a surprised way he jumped on his horse and galloped off, leaving me to mount my half mad charger and get my team out as best I could. That boy developed into one of the best soldiers in the Command and, until the end of the war, was up near the front in every engagement. It was his baptism of blood, and his confirmation followed immediately after it. This was one of the ways a be ginner had to be initiated into our service.

Так напарник автора бросил его с распутанными лошадями самого, или увел часть упряжки?
Если он трус, тогда концовка неясна.
Всего в упряжке было 4 лошади. - это для информации.