By 1870 what type of organization had taken over mining in the american west?

After the California Gold Rush that started in 1848, the waves of people (Called the forty-niners) looking to get rich quickly arrived, and by 1849, they have extracted most what was known as "easy gold".

After this period, the mineral's extraction was far harder and required more destructive and elaborated methods. This situation benefited wealthier individuals that opted to form massive corporations in order to get the most out of the mines.

The result of the birth of these organizations was that they transformed the mining industry by creating large national networks of production and finance.

So the answer is: Corporations.

2686-2181 bce-- "egyptian civilization developed along the nile river in large part because the river’s annual flooding ensured reliable, rich soil for growing crops."

1069-664 bce-- "ancient egyptians developed wide-reaching trade networks along the nile, in the red sea, and in the near east."

“a committee reviews the bill and marks it up to make it more viable and to reflect interests