Hi Dingo & All,
NGC 4755 was discovered by Lacaille but as you can see from this Wiki page:
http://en.wikipedia.org/wiki/NGC_4755
It received its moniker from John Herschel who remarked: "a casket of variously coloured precious stones". Back when I was growing up in astronomy, it was more commonly known as
Herschel's Jewel Box.
You can read, read and read to you heart's content about the history and ... everything else about glorious open cluster on one of Andrew James pages here:
http://www.geocities.com/ariane1au/Page001.htm
Wonderful resource!
Best,
Les D