If it's serialed at 405XX, it is a .38 Military & Police Model of1902-1st Change. 33804-62449, they were made between 1903-1904, I would guess your from late 1903? Should be a round butt, grips are checkered hard rubber, example no.43953 has a small leaf spring trigger return(don't know if yours will have this or not). The first square butts started in the middle of these at around 58000. This one is worth a letter to Roy Jinks. Info is quoted from SCS&W(Bible) 3rd edition. By the way, the two numbers on the frame and again in the cylinder window may both be serial numbers, if it was repaired at factory. The letter to Roy will verify if so?
But, if it's actually 489XXX it's a .38 Military & Police 4th Change. 1915-1942?
Good pictures would help determine for sure what you have?
HTHs Steve
Steve