la vista permite ver momentos de hace 100 años y harry deduce la posicion de un tirador por su aura

I nodded to her and looked up the mountainside—and then I shook my head
and drew up my Sight.
At once, my vision cut through Luccio's bewildering haze as though it had
never existed. I could see the mountainside in perfect detail—even as it was
in turn partially veiled by the vision my Sight granted me, which showed
me all the living magic in the world around us, all the traces of magic that
had lingered before, including dozens of imprints made in the past few
days, and hundreds of ghostly glimpses of particularly strong emotional
images that had sunk into the area during its heyday. I could see where the
girl who now lay shuddering with a bullet in her had tried to call up raw fire
for the first time, near a scorch mark upslope. I could see where a grizzled
man, desperately addicted to opium and desperately broke, had shot himself
more than a century ago, and where by night his shade still lingered, leaving
fresh imprints behind.
And I could see the little coiling cloud of darkness that formed the inhuman
energy of the attacking ghoul, running hot on the emotions of battle.