First you have to determine the make and model. Go to the library stacks and find The Standard Catalog of Firearms. Look through it and all the other books on that shelf until you find its picture. These books will tell you the range of dates this model was manufactured. If the gun has a serial number, you may find a listing that shows the range of serial numbers for each year. Or maybe not. Many old guns did not have serial numbers, some were numbered but the same numbers used several times, and some manufacturers' lists have gone to the recycle bin long ago.
@ 112 years old
Try Old Western Scrounger.
32-33 years old.
You will have to call S&W with the sn to find out.
Where did you find the serial number?
Try Old Western Scrounger
If you call S&W they will tell you.
1911 police pistol 32/20 double barrel
No published sn data
In the owner's manual
Look on the butt of the revolver