So much better in color than it would have come out in bw, in my opinion - and i don't really like color photographs that much usually. And brass, which is why this is so important in color, is a magical alloy. Surprising, though, is that brass even being an alloy is still so soft that the rubbing does wear it down rather quickly when used as a bearing. Don't really get how this all works, but the photograph is just terrific stuff. Keep the metalwork coming HiHo, nice stuff you are putting in gallery, whether it is heavy metal or muscle mounts.
I believe the brassy stuff is actually bronze; a much tougher material. Plus most of those later locomotives had some sort of fancier lubrication than running around with an oil can!
'Not that knowledgeable, DWT, but I think you're right. 'No idea what makes tin/copper so much harder than zinc/copper. 'Still strikes me that w/ all the wonderful stuff we discover - I suspect we forget more that we used to know about such things.