The Olympic class ships’ fourth funnels were not completely for decoration. Although they were not located above a boiler room for exhaust, they were placed aft of the third funnel to accommodate areas that required some sort of light ventilation like the kitchen and things of that sort.Interesting that in the first video you can see smoke coming from all four funnels. I have always read that the fourth funnel on the Olympic-class ships was a dummy funnel but clearly it must be venting smoke from either the engine room or perhaps the galley. So that should mean that all four funnels, at least on the Olympic at this stage in her career, were actually "working funnels".
Lots of stokers would have been out of a job. I imagine it wouldn't have been a popular conversion. The lucky few that stayed on would have had a much easier time of it though.>>By 1929, I think Olympic had been converted to run on oil or diesel instead of coal, and her 4 funnel might have been used to help vent fumes from the engines.<<
Not really. The change in the fuel only effected WHAT fired the boilers. How the effluent was exhausted was unaltered. There was no reason to change it.
The fuel the ship would have run on would have been the heavy marine oil of the day.
There were very few fumes from a steam recip engineroom, but the ventilation did go up the 4th funnel, along with the galley smoke. There's bound to be a chef burning something on a daily basis!By 1929, I think Olympic had been converted to run on oil or diesel instead of coal, and her 4 funnel might have been used to help vent fumes from the engines.