Complex sentence: Capital and labor each chose one of three arbitrators under the act; if they could not agree upon a third, the government would-the Chair of the Interstate Commerce Commission and the United States Commissioner of Labor acting in concert to make this choice.
Split into simpler sentences: Capital and labor each chose one of three arbitrators under the act; if they could not agree upon a third, the government would. The Chair of the Interstate Commerce Commission and the United States Commissioner of Labor, acting in concert would make this choice.