The work was done on piece wages, and the girls at first protested against the nine-hour day, fearing that their pay envelopes would suffer.

To their astonishment they earned as much in nine hours as they had in ten.

In time the employer cut the working day down to eight hours and a half, and in addition gave the girls ten-minute rests twice a day.

Still they earned their full wages, and they continued to earn full wages after the day became eight hours long.

The employer testified before the United States Industrial Commission of 1900 that he believed he could successfully shorten the day to seven hours and a half and get the same amount of work accomplished.
What can you do against testimony like that?
The Consumers' League convinced the Supreme Court of the United States, and the Oregon ten-hour law was upheld.
The importance of this decision cannot be overestimated.