Seems to be .357 (.38)
"*Iver Johnson's Arms & Cycle Works* --Fitchburg, Mass, U.S.A--" is on the top of the barrel rib, in two lines of text.
Exposed Hammer
5 shot break action
Owl on grip is facing toward shooter
Finish is mostly missing, but it looks blued
SN is T1187XXXX under grip, with 1187X on the trigger guard
Cylinder is just under 1&1/4 inches
Single and Double action
What do I have? When was it made?

A cheap .38 S&W worth < $100. Have fun shooting it.

Should be pre-war with"bicycle" still part of the name.

Safety hammer model .38 s&w cal.

Remove the grips and look at spring.

If it is a coil spring it is 3rd gen and safe with smokeless powder.

If it is leaf spring it is older and designed for black powder only.