Our instructor, Marcia, is fond of using Payne's Gray and we have exercises that call for its use. With all the tubes in my collection, I still had to go out for a tube. No problem there as I simply love buying supplies.
"William Payne (March 4, 1760 – August 1830) was an English painter and etcher who invented the tint Payne's grey."
"Among the innovations with which he is credited were "splitting the brush to give forms of foliage, dragging the tints to give texture to his foregrounds, and taking out the forms of lights by wetting the surface and rubbing with bread and rag". He also abandoned the use of outline with the pen, but the invention by which he is best known is a neutral tint composed of indigo, raw sienna, and lake called Payne's grey. His methods were regarded as tricky by the old-fashioned practicians of the day. but there is no doubt that he did much to advance the technique of watercolour painting, and was one of the first 'draughtsmen' to abandon mere topography for a more poetical treatment of landscape scenery."
Winsor & Newton's Payne's Gray has a bit of a different makeup:
Chemical description: Copper phthalocyanine, Carbon black, Quinacridone
Color index name: PB 15, PBk 6, PV 19
Here's a bit of play with that color. A graduated scale, some wet in wet, dry brush, and a meld about a wash of thalo green.
Wikipedia contributors. "William Payne (painter)." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 7 Jun. 2010. Web. 10 Jun. 2010.