As a foodie, I love this. In many respects, menus don’t seem to have drastically changed over the past 175ish years but it looks like a “Boiled” category was common early on, which I assume was because boiled foods were popular and/or easy for restaurants to make in bulk.

> menus don’t seem to have drastically changed over the past 175ish

After looking at a dozen of the ones from the Boston area I have to say that my sampling disagrees with yours.

Turtle, Sweetbreads, Venison, Mutton are all things that would get a foodie OUT to eat today and seem to have been much more common then.

Also much of what I am seeing as "boiled" is going to range from "poached" (salmon) to "braised" (some of the tougher organ meats). Stumbling across a "boiled" chicken, served with rice and cucumbers in an 1800's menu made me jump to "Hainanese chicken rice". That preparation seems exotic to the modern American style but might not be as alien 100 years ago (Flavoring aside).

One massive change is that there is almost no ethnic food on these menus (unless you include French). I looked at some of the LA menus and there were zero Asian, Mexican, or Italian dishes. It's impossible to imagine today that you could look at a bunch of hotel restaurant menus in LA and not find at least some dishes that were inspired by those cultures.