Lloyd's building consists of three main towers and three service towers around a central, rectangular space. Its core is the large Underwriting Room on the ground floor, which houses the Lutine Bell within the Rostrum. Also on the first floor is loss book which for 300 years has had entries of significant losses entered by quill. The Underwriting Room (often simply called "the Room") is overlooked by galleries, forming a high atrium lit naturally through a huge barrel-vaulted glass roof. The first four galleries open onto the atrium space, and are connected by escalators through the middle of the structure. The higher
Points of the compass compass roses will typically have the initials T, G, L, S, O, L, P, and M on the main points. Portolan charts also colour-coded the compass winds: black for the eight principal winds, green for the eight half-winds, and red for the sixteen quarter-winds. Each half-wind name is simply a combination of the two principal winds that it bisects, with the shortest name usually placed first, for example: NNE is "Greco-Tramontana"; ENE is "Greco-Levante"; SSE is "Ostro-Scirocco", etc. The quarter winds are expressed with an Italian phrase, ""Quarto di "X" verso "Y" ( one quarter from X towards Y), or