Does anyone know the context this was written from? No sense compared to a 10 hour work day? 6 hour? Roughly 8 hours a day broken up as convenient? However

Does anyone know the context this was written from? No sense compared to a 10 hour work day? 6 hour? Roughly 8 hours a day broken up as convenient? However long it takes to get a well-measured hunk of work done? The article doesn't really mean anything without this.