Hi!
Any ideas about how to make the shape of an air pollution plume like the shape illustrated in this figure coming out of a smoke stack?
Maybe like this?
I drew a circle at the top of the chimney, a path for the centerline of the plume, and an ellipse at the far end. then I used Fredo6’s Curviloft to create the plume geometry.
That looks great! I’ll have to look up Curviloft. Thanks 
Get it and the supporting LibFredo6 from Sketchucation.
Another option if you want to play with the shape a bit because you might want to consider different wind strengths would be another Fredo extension, Radial bend.
Wow! Thanks!