Herb Kelsey Wrote:
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> They were classified as 45 1/2 class.
> They were later upgraded with extended smokeboxes
> and straight stacks and were reclassified with the
> other 4-6-0's of the series as 47 Class.
As I understand the class 45½ were engines158 through 165, built to Baldwin class 10-22D drawing 2. They were quite different from the later ten-wheelers, being lighter with a smaller boiler and fire box, but a slightly longer driving wheelbase. All of them were delivered with diamond stacks and built-up beaded domes. None of them lasted into modern period (ie, the 1920's and beyond) so they don't garner much attention these days.
The others were all of a larger pattern, ordered later on. Engines 166-168 were ordered in one batch, then engines 169-177 were ordered in a second batch some months later, but both batches were built to Baldwin class 10-22D drawing 3. Engines 167 and 168 were indeed ordered with diamond stacks as-built while the others had straight stacks with extended smokeboxes, but otherwise all 12 of these later engines were built to the same plans. All of them had smooth cast domes right from the start. It is certainly possible the D&RG could have initially classed the earlier 47's with the class 45½ machines before changing to the class 47 designation*; I'm not necessarily calling anyone wrong, only clarifying the distinction between the two rather different models of D&RG narrow gauge ten-wheelers.
*The D&RG did this elsewhere: Engines 400-411 and 417-422 were both class 70, even though the two batches were built to very different plans.