Urban architecture is the supreme public art. Not only is it there for all to see; it is impossible not to see. Yet the interiors of buildings, despite being as essential to the overall conception as the outside, often contain glories that are unimaginable to those who lack privileged access.

A spectacular example is the new Bloomberg L.P. headquarters at Lexington Avenue and 58th Street, also known as One Beacon Court, which brings together 3,700 employees who formerly were dispersed in five locations around the city. Though its exterior was conceived by Rafael Pelli of Pelli Clarke Pelli, its interior is the work of Todd deGarmo and Tom Krizmanic of Studios Architecture. Occupying nearly 700,000 square feet, the office space extends across several floor plates of the new building, whose two halves cover the block formerly occupied by Alexander’s. As with all the best design, every detail, every screw, every square inch of carpeting seems to have been invested with intelligence and thought.

A few days ago, I visited the building for an appointment. Having arrived in the austere granitic lobby, I took an elevator up to the sixth floor, where the first thing I noticed was the way the elevator bank glowed with a soft purple light and turned red or green as the elevator car rose or descended. In the context of this long, bustling corridor, a black, low-lying chandelier in the baroque style struck a distinctly incongruous note. But it was only the first of many surprises that awaited me.

The second was the affable security man who, despite the crowds, knew my name (the security detail downstairs having alerted him to me coming). He invited me to wait in the two-story common area, a 40,000-square-foot white space whose skylight is supported by a series of steel radial trusses. This is the inside of that dramatic, conical horse-shoe drum that bisects the exterior of the Bloomberg Building between Lexington and Third Avenues.

By design, visitors are immediately thrust into the tumultuous comings and goings of the employees. As part of the programmatic egalitarianism of Bloomberg, no distinction is made between the front and the back of the office: Everything is out in the open. No less striking is the long row of concessions stands offering free snacks to employees and guests alike. This has to be seen to be believed: In addition to salads and the like, there are long, orderly rows of dazzlingly wrapped goodies like SnackWells and Oreos, which merge into a rainbow of clashing hues.

Food aside, a minimalist aesthetic pervades the place. It is a zone of spare right angles and opulent emptiness in which clean lines are qualified by a few well-chosen curves. But among these apparent austerities are sudden oases of sumptuosity: vases filled with the finest orchids, gleaming aquariums teeming with serene tropical fish, a pond stocked with koi and a frog. Well-placed artworks (including a huge titanium cloud created by Inigo Manglano-Ovalle) and an amazing spi ral escalator, one of only two in North America, lend textural richness to the unfolding space. It is the reflex of the eye to take in not only the beauty of these amenities, but also an intuited sense of their expense.

Of course, offices, even those as acutely design-conscious as Bloomberg, exist so that workers can work. Here too we find evidence of Mayor Bloomberg’s management philosophy, which also informs the way he has arranged City Hall. There is no hierarchical arrangement of offices – not even partitions between the executives and the rank and file as they sit at long desks equipped with computer monitors. Among the various sectors are sheer glass monoliths of expanding fuchsia, green, and gold. Each sector has one or more soundproof glass chambers to which any employee may resort for a private conference.

The single most astounding thing about the design of the place is the uninterrupted sightlines that make it possible to see straight across almost from Lexington Avenue to Third Avenue. The logic and the consequence of the design are immediately evident: All 700,000 square feet seem ablaze with activity, a veritable hive of ceaseless energy. Despite its modernist severity, the building seems to foster and enhance the energies and creativity of all who inhabit it.

Throughout the history of corporations, architecture and design have been invoked to influence public perception. For years, the granite columns that adorned our banks suggested the august trustworthiness of the institutions they housed. At the Bloomberg headquarters, in its subtle and efficient way, such details as the tropical fish, the orchids, and all the Oreos you can eat give off an overwhelming sense of style and competence. More subliminally, but no less powerfully, they communicate a heady sense of the financial might, the wealth that is the Bloomberg empire. Most importantly, they attest to the beneficial effects, spiritually no less than financially, that thoughtful design can have upon the human beings who inhabit it.

jgardner@nysun.com