In 1929, and still today, some of these floors house various types of telephone equipment. When the building was new, the second floor held the step switches for 40,000 customers in downtown Denver. This floor had to have a specially reinforced floor and a 16-foot ceiling to house the 11-foot frames of the switching equipment, along with space above for cables. Over 2,000 tons of equipment sat on this floor.

The fourth floor was primarily occupied by the “long lines” (long distance) department of AT&T. About two hundred long distance circuits came into this floor; each had to be tested, and if found in trouble, the test man would call an equipment man, lineman or cable maintenance man and work with him to clear the trouble in the shortest amount of time.

Three national radio program supply networks were routed here and were closely observed to prevent interruption and keep quality and volume at their best. There were also about one hundred “special contracts” utilizing “telephone typewriter” and Morse routed and monitored on this floor. These contracts were set up with “the various press associations, the government and commercial firms such as brokers, packers and manufacturers.”

Today, highly efficient compact and reliable electronic switches handle millions of calls daily.

Various supervisors’ offices were located on the sixth floor, along with the official company telegraph office and its three operators. Part of the Engineering Department was located on the eighth floor, as well as the Western Electric Company Installation Department, whose function it was to “install central office equipment in all the territory in which the Mountain States Company operates.”

The tenth floor held various offices and departments.