1. Grant is right - this book does a great job reviewing the contributions of pre-marginalists like von Thunen, Cournot, Dupuit, and Gossen. I knew von Thunen from my undergraduate history of thought class (I did my paper on spatial economics, which goes back to him), and of course Cournot is familiar. I knew Dupuit somewhat through Grant and didn't know Gossen at all. Sandmo is excellent at outlining precisely what each contribute, what each missed, etc. It is impressive in most cases how much more they actually perceived than the marginalists themselves.
2. Here's a nice quote from Jevons that drives home the stupidity of the cardinal/ordinal arguments, because everyone agrees that preferences themselves are ordinal even if we choose cardinal functions to represent them. He writes: "To me it seems that our science must be mathematical, simply because it deals with quantities. Wherever the things treated are capable of being greater or less, there the laws and relations must be mathematical in nature". Of course some things go beyond this ordinality (like prices or quantities), but in terms of preferences, as I've said many times on here before, the preference relations are ordinal, the utility functions (which nobody believes actually exist but are a modeling convenience) are what's cardinal.
3. Menger is presented by Sandmo as being unaware of the advantages of modeling with continuous, cardinal utility functions. The sketch on these authors is sometimes brief so it's not clear why, but he refers to it as something that he was not aware of. It's amazing to see the simply things that early scholars missed, just because it hadn't been discussed much before (Jevons, for example, is described as being just one very easy step shy of a full general equilibrium model of the sort that Walras had. Jevons wasn't a dummy any more than Menger was, but sometimes coming up with this stuff for the first time is tough). So does anyone know if this is true? Does anyone know, for example, if Menger actually said "well you could do it ordinally and you could do it cardinally and ordinally is definitely the right way to do it" - because if he didn't make such a ruling it seems to me (1.) Sandmo is likely right, and (2.) a lot of the Austrian preoccupation with this question is window dressing after the fact on a point that was never particularly important to Menger in principle the way it is important now as a principle.