Stratus, in the historic lobby of 315 Montgomery in San Francisco, commissioned by Vornado Realty Trust. Stratus, on view from the street 24 hours a day, consists of a layered array of brass tubes that contrast with the ornate architecture of the lobby in its simplicity. The brass tubes are punctuated by a cloud-like pattern of laser-cut holes; each tube houses a custom LED and diffuser assembly and is programmed with a subtle light pattern that simulates air flow. The two layers of brass tubes are staggered, giving the animated light a three dimensional effect, which is enhanced as the light from one tube reflects off of its neighbors. During the day the assembly comes together in the shape of a light organ, while at night, the tubes fade into the background and the cloud-like LEDs appear to flow through the back wall of the lobby. 315 Montgomery Street, part of the Bank of America complex, is a 16-story office tower in the financial district of San Francisco which was originally built in 1922.