The Romans didn't use bricks so much as a structural material as a decorative facade..
Concrete made up the "bones" and the outside face was "prettied up" with fancy brickwork, often stamped or pressed with designs to make them look even better..
You're right about the concrete..
Cement was first used by the Assyrians, and the Egyptians were familiar with it as well..
The Etruscans used "additive" in their cement, so it might qualify as a sort of concrete, but concrete is defined by the use of "aggregate", i.e., the crushed rock, small stone and gravel added to the cement..
And that is, truly a roman "invention" or discovery, depending on how you look at it..
Something else the Romans did not many know about..
They learned that concrete / cement could be made "stickier" with the addition of gluten..
In the case of the Romans, they used, for the most part, wheat, boiled down into a thick sticky liquid.. This was then added to the concrete (or cement) mix to insure superior adhesion..
The Chinese, I believe, did the same thing, using another, similar ingredient.. Rice..
Again, boiled down to make rice glue, then added to the cement / concrete..
Thanks for all the great detail on the concrete. I saw something on Discovery or the History Channel about it on "inventions" show.
It's hard to undersand how the knowledge completely died out sometime between the fall of Rome in the 5th century and the late 18th century and the invention of Portland cement in 1824.