It was a very bad working environment. If their hands went the wrong way in gears they could loose their hand.
The working conditions weren't good at all. For example, the floor wasn't that great. It was wood so full of splinters and dirty and dusty. They weren't rich of course so most didn't have shoes.
They weren't paid enough. Since they were children they were payed a lot less than adults.
Children were the most busy ones because they had to go to school then straight to work, so they barley had any sleep. If you met those children or seen photos of them, you could see the very dark circles under their eyes.
Hoped I helped!