Complex sentence: As a result, the Bell System as a whole developed into an unorganized system of many differing local numbering systems that impeded the efficient operation and interconnection of exchanges into a nationwide system for long-distance telephone communication.
Split into simpler sentences: As a result, the Bell System as a whole developed into an unorganized system of many differing local numbering systems. The diversity impeded the efficient operation and interconnection of exchanges into a nationwide system for long-distance telephone communication.