Simultaneously, mine development needed to proceed.
The iron mine in Roanoke was still maintaining good production. The problem now wasn't on the iron side.
"What about stone?"
"Given the scale of either bridges or breakwaters, stone alone would be difficult. We'll need cement."
Cement to be used in the construction of bridges and breakwaters.
Fortunately, unlike what Kin Issei had thought, 17th-century people were well aware of cement's existence. Since it had existed since ancient Roman times, they couldn't help but know about it.
However, cement was mostly used as exterior material or architectural adhesive, and rarely used for actually constructing various facilities.
Still, they did know that cement could be mixed with water and various aggregates to harden into concrete, and structures could be raised with it.
They just lacked practical experience using it.
