I found these four 1918 glass negatives not too long ago on eBay. On my old computer changing a negative image to a positive image was so simple, just a click of a button. I'm a bit embarrassed to admit it but with my brand new computer I've yet to figure out how to do it.(window 8.1) I've looked and looked and found all kinds of editing tools except to turn reverse negative images.
eBay
eBay
eBay
eBay