The Sound of Condensing Locomotives

Alas no, if only. I had a conversation with the driver of a Dean Goods which had been converted to condensing mode to haul huge guns mounted on rail trucks on Dover cliffs during the war - they didn't want exhaust steam to give the position away. He gave me the tip about the crackling sound. When still a child I saw an ex-GWR pannier tank hauling an engineer's train through Tower Hill station, but my memory lets me down on the sound - I don't even know if they were fitted with condensing gear?
Please enlighten me about the SAR 25s.
There's an amusing story in Alan Jackson's 'London's Metropolitan Railway' about when Aldgate station was built, they had the troughs into which the boiling condensing water from the Beyer Peacock 440s was dumped. These troughs originally connected with the common sewer down to the Thames...until houses further down the sewer pipe found that 1000 gallons of boiling water rushing down created a nasty shock for anyone communing with Nature at the time. The Metropolitan was required to build its own sewer quite rapidly.

Very many thanks for those links. Yes, I was being slower than usual in failing to pick up your reference. I've got an article somewhere by a fireman relating his experience of suddenly being confronted with one of these locos; he had a steep learning curve but succeeded in the end. As you mention, these were much more sophisticated than the denizens of the Widened Lines, with exhaust turbines powering forced draught for the fire and the cooling fans as well; I believe they also has oil traps to make sure that the lubricants in the exhaust steam didn't get recycled back into the boiler. The arrangement on the Beyer Peacocks was simpler. The exhaust steam pipes entered the side tanks and ended above water level, but just beneath it another pipe led down under water and at the bottom bifurcated and led fore and aft, but perforated. The idea was to let some steam condense under water and some to go over the water surface...presumably this split was to avoid back pressure. Oil droplets were deemed acceptable as water changes were frequent, Aldgate, Edgware Road and (I think) South Kensington.

That's very kind of you. While you are looking at valve gear on the Beyer Peacocks, any information on the Gibson and Lilley gear that they had (replacing the original Stephenson), would be VERY much appreciated.