I am reading Blood Meridian and McCarthy makes a mention of the "possibles" or as I understand it the supplies that cowboys would carry with them on the trail. I am wondering what this would consist of? Any books or reference material that might help me in my search would be greatly appreciated.
Not a great deal of cowboys in the early to mid 1800s. Plenty of fur trappers in the early 1800s usually now called mountain men. Good number of mining prospectors in the mid 1800s mostly based around California and Nevada. Mormon settlers in fairly large numbers from the mid 1840s. I'm going to answer for mountain men because the heyday for "cowboys" would for me be the mid to late 1800s.
Most of the time "possibles bags" were called shot bags and usually carried shot, flint and steel and some dry tinder. They were mostly used for hunting pouches. You could carry whatever you wanted in your own pouch so some people also carried sewing supplies or equipment to make lures and sometimes first aid supplies such as a bandage.
I found a website for "mountain men" that has a pretty exhaustive list of all supplies compiled from several inventories. It also includes references to the original sources.
From the Complete Blackpowder Handbook:
"The possibles bag was probably a larger pouch in which could found a bit of tobacco, spare gunpowder, flints, patching materials, fire-steel for starting the well-known flint 'n' steel flame...
I remember looking that one up when I read Blood Meridian too. Apparently it's a common term among those in the know. Google "possibles black powder" and there are a lot of hits.
Aren't a the Glanton gang essentially naked through a lot of that book? Like their clothes all rot off and they're starving to death? Woo, good times.
To anyone interested in the history of the West, Blood Meridian is a terrific book. A complete inversion of the usual cowboys-and-indian story.