It was in America,therefore,that the great advances in nineteenth century agriculturalmachinery first came.that 后面的语序是不是有问题?应该是the great advances in agricultural machinery in the nineteenth century吧?

It was in America,therefore,that the great advances in nineteenth century agriculturalmachinery first came.that 后面的语序是不是有问题?应该是the great advances in agricultural machinery in the nineteenth century吧?
It was in America,therefore,that the great advances in nineteenth century agricultural
machinery first came.that 后面的语序是不是有问题?应该是the great advances in agricultural machinery in the nineteenth century吧?

It was in America,therefore,that the great advances in nineteenth century agriculturalmachinery first came.that 后面的语序是不是有问题?应该是the great advances in agricultural machinery in the nineteenth century吧?
原句没什么问题.
in nineteenth century 是advance 的定语
in agricultural machinery 也是advance的定语
两者孰前孰后都没有关系.
供参考.

in the nineteenth century 放在居中或句末都不会造成语法错误，关键是看它修饰的成分

不是有个first came吗，所以原句是对的

原句是the great advances in agricultural machinery
19th century是修饰machinery。
19世纪农业技术的巨大优势先来到（的地方）是美国。