Lots of chisels; what are they for and how do I sharpen them?

[Gant]

Having restored my father-in-law’s old tool chest, I’m now checking out the chisels that were in it. There’s quite a range, including 5 Stormont crank gouges and a couple of Marples (and a very fine Marples straight gouge) chisels from Woodcock, Wallins, Ward, and Marples, an Addis swan neck and a ‘thing’ from Sorby. What is that, and what is it for? It has a very strange tip with oblique bevels (see photos).
Also, all the gouges have bevels inside the curve. How do I sharpen these without curved stones?

 

[Orraloon]

Some beauties there. The oblique bevel one has me stumped. Never seen that before. Must have been reground for some specific job.
As to sharpening the gouges get some dowel about the right size for the curve and wrap fine sandpaper round it. A look online should find you a curved stone. (slip stone)
Regards
John