Personification is the literary technique where an author makes it seem as if inanimate objects are animate -- that they have qualities that only animate objects have. Given this definition, you should be able to see lots of personification right from the start of the story.
Here are some examples:
- The armies were "wrestling." Armies don't wrestle -- people do.
- The artillery battery was "arguing" with the enemy's artillery.
- Later on, the guns have "demeanours of stolidity and courage."
- One of the officers is riding a "sober and reflective" horse. Horses are, of course, animate, but they can't be sober and reflective -- those are human attributes.
- The artillery shells hate the meadow.