Not that different. You find a nearby river and build a limited channel to draw water from it.
The reason there is that walls/towers generate multiple rolls, so thats the route to go for incremental progress. It won't get you concrete in one shot but it would develop
Dam gives you one big roll, but if you don't have the ingredients(Kiln, Limestone, suitable filler), you'd simply develop something else as the solution entirely, and a large investment. People have built dams with no more complex mortar than mud
That's one thing I definitely missed. Still need the limestone though. If we have limestone available via Survey, then yes, a Main Art Patronage would probably discover something. As would Study Metal(Limestone makes smelting iron from the ore that much easier).
Yep.
Basic steps to Mortar now, revised:
1) Obtain Limestone. We will know it as the "white stone", "flowing stone" and the bitter water. Shells and corals do not provide usable quantities for production, but potentially can be substituted for limestone in stage 2 and 3 with luck.
-This is a necessary prerequisite
-This is unlikely to be traded for. Nobody would trade it since it's rock and bulky.
-This can only be found by Survey. It can be discovered without knowledge of it's utility in metal extraction or mortar production, as limestone is an attractive construction material.
2) Learn that Limestone transforms to lime when under dry heat
-This is an optional prerequisite, it can be discovered by accident during the smelting of ore, manufacture of bricks or baking of pottery.
-This can be Traded for potentially. The Xohyssiri may have the technology, as might any metalworking faction.
-This can be obtained through Art Patronage, if you have limestone, as limestone gets experimented on for as glazing materials.
-This can be obtained through Study Metal, if you have limestone, as limestone gets experimented on as a potential metal ore(due to being colored, besides, it's technically calcium ore
).
-This has a low chance of being obtained through the study of mine tailings, as using limestone based pits will cause a vigorous and alarming reaction to prompt further research
3) Learn that Lime reacts with other materials to form cement/concrete.
-This is an optional prerequisite, it can be discovered by accident during the same time as Step 2.
-This is unlikely to be traded for as the reaction of lime will not be something that foreigners will be seeing. However a spy mission is not impossible with more Blackbirds.
-This can be obtained through any major construction project once Lime is discovered. The bigger the project, the more likely. Projects involving water or tall constructions have a boosted rate:
--Main/Double Main Walls
--Main/Double Main Towers
--Main/Double Main Trails
--Main/Double Main Snails
--Dam
--Aqueduct
--Saltern
-This can be obtained through Art Patronage via glazing experiments.
-This can be obtained through Study Metal via smelting experiments.
As such, you can see only the initial step is invariable. You need the stone to do anything else. But once you have it, it's merely a matter of time to notice.