Is this structure right?

[Lyf]

Would you pls explain for me the meaning of this sentence:"In agriculture, the transformation was marked by the emergence of the grain elevators, the cotton presses, the warehouses, and the commodity exchanges that seemed to so many of the nation's farmers the visible sign of a vast conspiracy against them."Is the grammar structure of the this sentence right

[Tdol]

It's right. The rise of the technologies and the business structures seemed to represent a huge threat to the farmers.