represents the approximate diameter of the top shade in decimeters. The second number indicates the decimeter used to create the middle and bottom shades using the 3:2:1 ratio. For example: A PH 5/5 lamp has a 50 cm top shade, a 31 cm middle shade (around 2/3 of 50), and a 16.5 cm bottom shade (around 1/3 of 50). The original models (with matching top and bottom fractions) worked well as ceiling lamps but they weren't suited for low-hanging use, like over a table, where the illumination area was too narrow and intense. To address this, Louis Poulsen released lamps in 1927 with larger top shade proportions. These wider lamps, like the PH 4/3 and PH 6/3, had a top shade from a larger model and a middle and bottom shade set from a smaller model. For example, a PH 4/3 lamp has a 40 cm top shade but a middle shade (20 cm) and a bottom shade (11.2 cm) created using the 3:2:1 proportions of a 30 cm top shade. The lamps were commercially successful and the royalties created the financial safety net for Henningsen to focus on his literary work. Literary career During the 1920s Poul Henningsen had his literary breakthrough. He edited the polemic left-wing periodical, Kritisk Revy (1926–1928, "Critical Review"), in which he and his colleagues scorned old-fashioned style and cultural conservatism, linking these themes to politics. At the same time he began as a revue writer praising natural behaviour, sexual broad-mindedness, and simple living. He made the Danish revues a political weapon of the left-wing without giving up its character of entertainment (the so-called PH-revues 1929–32). Henningsen created the PH Grand Piano (Danish: PH Flyglet) in 1930. Poul Henningsen did a groundbreaking design with the PH Grand Piano that is characterised by the transparent glass-lid, the leather rim and the steel legs. The PH Grand Piano departures significantly from the traditional grand piano or the "black box". Poul Henningsen wanted to open up the piano and bring out the beauty of the musical parts. It has become a Danish design icon and reflects an important contribution to the Bauhaus design tradition. In 1933, he edited his most famous work What About Culture? (Danish: Hvad med Kulturen? ), a polemic, audacious, and urgent criticism of Danish cultural life and its snobism and passion of the past in spite of all the efforts of the Modern Break-Through.