Hi There,
It looks like you have a .38 S&W Safety Hammerless 3rd. Model.
These were made from 1890 to 1898. Serial number range for
this model is 42484 to 116002. The only way to know for sure
when your revolver was sold is to obtain an historical letter
from the S&W Historical Foundation. Judging from your serial
number, I would say mid-1890's.
Cheers!
Webb