Dutch Police Revolver (with safety!)

This Dutch police revolver is an interesting example of technology being used as an element of police policy and procedure. The Dutch police administration in the late 1800s/early 1900s decided that officers should carry a blank round in the first chamber of their revolvers, a tear gas round in the second chamber, and actual live bullets only in the 3rd-5th chambers. This led to a problem of ensuring that officers were able to easily confidently know which type of ammunition they were firing at any given ti