Hi Jessup,
I can't tell you anything about the Norris plane that Jimi hasn't already said far better than I could, but I can offer a thought or two on the Ibbotson chisel.
It is indeed a patternmaker's paring chisel. Chisels are usually 'sized' by the width of the cutting edge, and that one looks to be a 2". The handle is 'London Pattern', gorgeous, and original. Hard to tell from the photo, but I suspect it's boxwood - often used in top-quality chisel handles. It's thin-bladed to make it lighter in use for paring - shaving bits off to make close fits between components, or to get an exact size. This isn't a chisel that would ever be used with a mallet, only by hand. If you look at the end of the handle, it probably has no mallet damage. The blade is probably tapered slightly both in width and thickness, wider at the cutting edge than the tang end, and thicker at the tang end than at the cutting edge. Those tapers were forged in by eye under a spring hammer - just by the hammerman's skill. That style of blade was common in the 18th century, but fell out of favour in the late 19th, so that may mean it was made in the early or middle 1800's rather than late 1800's.
Patternmakers were among the most highly regarded of the woodworking trades. Patterns are the first stage in making metal castings - a wooden model. The pattern was embedded in sand in a wooden or metal box, then the box/sand/pattern lump inverted, and the pattern drawn out. Molten metal was then poured into the resulting hole, and when it had cooled, the sand knocked off to leave the casting. Complicated castings involved intricate patterns with many bits fitting together, cores that could be installed in the mould to make hollow castings, and so on. Because metals contract as they cool, the pattern had to be made slightly larger than the finished casting was required, and because the pattern had to be drawn from the sand, it had to be made slightly tapered. So patternmakers had a lot to get right - hence their need for tools that could adjust bits of wood to very close measurements!
I know this because I inherited a very similar chisel (mine's a 1 1/2", by I&H Sorby) from my grandpa, and I know he got it very secondhand. The handle on mine was beech, and rotten, so I replaced it in rosewood, using a shape very similar to yours. It's one of my favourite tools, and I won't part with it for anything. But yours is better than mine - original handle, lovely patina, respected maker - the collectors would fall over themselves for it.
Should you ever take up cabinetmaking (other than desk modification!) you'll find that this chisel will take a wondeful cutting edge. Keep it safe for the finest work - it's a VERY fine tool.