It is truly amazing that she survived at all since all the other five of the class were out of service by 1938. It always amazes me that these engines built in 1887 with more modern technology were outlived by three of the C-19 class of 1881. A lot had to do with weight and tractive force, I imagine.
Interestingly the July 1948 timetable number 6 of the RGS shows 40, 41 and 42, along with the 340 class, all rated the same for tonnage. This whole tonnage table is a little suspect, however, as the 300-306 are shown (they'd all been gone for ten years!) and they were rated the same as the C-18's! The C-17's and C-18's were rated for substantially higher tonnage than the C-19's. Go figger.