Thanks from me, too. I use this sort of thing for reference. The ads are as interesting as the carriages. It's amazing how many "support" items were necessary to maintain these supposedly simple vehicles: springs, felloes, spokes, truss loops, coach steps, and on and on. I'm curious about the "Monson's Patent Extension Gas Fixture" on page 39. It says the extension is not a "sliding tube" but uses "the turning of tubes one within another." Damned if I know what that means. It seems like a gas-tight seal would be hard to maintain, but the thing has been adopted for use in Government Buildings. It says so right here.
Link to the book:
Illustrated Catalogue of Carriages