Which is one reason that factory work was dangerous in the 1800s?

One reason : Machines were too difficult for workers to use.

abraham lincoln, according to anyone who was connected with agriculture, represented the worst of northern politicians. shortly after lincoln was elected, south carolina seceded from the union. they along with other southern states, retained their anger. in a way, it was their own fault: the democrats were split in the south. some wanted slavery to be extended in other states that were about to join the union and some didn't want it badly enough. lincoln had a solid backing from his party: the republicans were united in not wanting slavery to be expanded.

new evidence is discovered.

oversights and errors are corrected,

new technology is applied to evidence.