If it is a 3rd Model (aka Wolf & Klar Model, or Model of 1926) the ejector rod will be enclosed by a barrel lug. If it is a 2nd Model the ejector rod will not be enclosed.
If the hammer and trigger are anything other than case hardened (plated in any way, polished, etc.) it has been refinished outside of the factory.
Give us more details such as the barrel length (measure from muzzle to front of cylinder). Look under the grips for any markings. If it has been back to the factory there may be a number such as 4.41 on the left side of the grip frame which would indicate that it was returned there on April, 1941.