https://archive.org/details/throughugandatom00purv/page/86/mode/1up

The picture is on page 81 of this, and it describes them as being hired to guard the train from some of the locals that it would be passing by. So these guys are here ready to fight and kill other humans

Also heads up for anyone going in to read this, the author’s language choices are almost comically colonial (though without slurs, in the few pages I read)