Re: DSP&P No.24

Como Wrote:
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> Well 24 had more tubes and operated at a higher
> pressure that previous locomotives, so I wondered
> if as they developed the concept this became the
> new standard so not just a South Park one off but
> an improvement they brought in that just so
> happened coincided with the construction of 24.


Interesting. I haven't directly read previously that the 24 differed from the other 14x16 2-6-6's. The majority of extant sources treat that group as equivalents. Such a difference as you suggest would potentially explain why I see things like differing boiler pressure values and specification differences crop up in various sources for that model. What do you know in terms of detail differences between 24 and its straight-boilered 14x16 siblings? Specifically was the boiler material changed from wrought iron to steel? Pressures much beyond the industry standard (for circa 1880) 125-135 pounds would've been highly unusual in an iron boiler, though not entirely unheard of.

Tube counts could be changed during overhauls/etc. It was not uncommon to remove flues that tended to become clogged up anyway (often the lower ones), or squeeze a few more in so as to improve steam generation. Is there any record on whether engines from this group altered their tube counts later on?