century through many changes of corporate ownership. Sometimes the shape of the funnel is used as distinguishing feature rather than just the colour. Cunard fitted ships of its Saxonia class with streamlined round tops to the funnels. Intended as an aerodynamic aid to keep exhaust clear of the deck the modification had very little practical effect but was retained because it made the four ships of the class immediately recognisable and gave Cunard a suitable modern image. There was a trend for 'designer funnels' on liners in the 1960s as fashion and aerodynamic advances combined to offer designers more options that the traditional cylindrical smokestack. The Italian Line fitted the liners Michelangelo and Raffaello with funnels topped by flat discs supported on exposed diagonal bracing while P&O's Oriana and Canberra had tall, thin funnels with aerofoil cross sections. In the late 19th and the first half of the 20th century the number of funnels became associated with speed and reliability. For this reason a number of the great liners carried additional false funnels that they did not need. Examples included the White Star Line's , Hamburg America Line's , and later the French Line's . In most cases there was only a single false funnel placed as the aftermost of the funnels. The false funnels did have more uses than simply aiding aesthetics however - a stoker who survived the sinking of the Titanic escaped the boiler room by ascending the false funnel, the aft funnel of Normandie housed the passengers' dog kennels, and Disney Cruise Line's Disney Magic's forward funnel plays host to a teens-only club. Naval ships A key part of the deception practiced by ships carrying out commerce raiding during both the First World War and Second World War was to disguise their ship's outline, and this included using false funnels or by changing the height or diameter of the actual funnel(s). Four naval ships with six funnels each were constructed in the late 19th and early 20th centuries: two Italia-class ironclad battleships operated by the Italian Navy from 1885 to 1921, and two Edgar Quinet-class armored cruisers operated by the French Navy from 1911 to 1932. Both had their funnels in two groups of three before and abaft of center. Macks A mack is a combined stack and mast, as fitted to some classes of 20th century warships. Although they can reduce top-weight, they have not