- center ▁walk - through ▁at ▁ground ▁level ▁separ ates ▁the ▁building ▁into ▁north ▁and ▁south ▁wings , ▁and ▁provides ▁a ▁view ▁of ▁the ▁De Ro y ▁Aud itor ium ▁from ▁Cass ▁Avenue . ▁The ▁first ▁floor ▁is ▁faced ▁with ▁buff - color ed ▁tra vert ine ▁mar ble , ▁and ▁the ▁second ▁and ▁third ▁stories ▁are ▁faced ▁with ▁cast ▁concrete ▁pan els . ▁N arrow ▁windows ▁are ▁in set ▁between ▁the ▁pan els . ▁The ▁outer ▁edges ▁of ▁the ▁first ▁floor ▁are ▁re cess ed ▁back ▁from ▁the ▁edge ▁of ▁the ▁upper ▁stories . ▁Th in ▁fre est and ing ▁columns ▁cl ad ▁in ▁mar ble - f le ck ed ▁concrete ▁ring ▁the ▁lower ▁floor , ▁and ▁meet ▁the ▁upper ▁section ▁at ▁its ▁edge , ▁serving ▁to ▁support ▁the ▁two ▁upper ▁flo ors . ▁The ▁columns ▁continue ▁up ward , ▁termin ating ▁at ▁the ▁top ▁of ▁the ▁building ▁in ▁a ▁project ing ▁fin ial . ▁ ▁On ▁the ▁north ▁side ▁of ▁the ▁first ▁floor ▁is ▁a ▁story - and - a - half ▁study ▁hall ▁en closed ▁in ▁glass ▁pan els , ▁with ▁a ▁me zz an ine ▁to ▁the ▁north . ▁The ▁southern ▁side ▁of ▁the ▁first ▁floor ▁houses ▁administrative ▁offices , ▁and ▁the ▁off - center ▁walk way ▁separ ating ▁the ▁two ▁sections ▁houses ▁plan ters ▁and ▁a ▁ben ch . ▁The ▁second ▁and ▁third ▁flo ors ▁are ▁used ▁for ▁office ▁space . ▁Two ▁double ▁glass ▁doors ▁off ▁the ▁walk way ▁open ▁onto ▁a ▁double - turn ed ▁st