Burglar alarms - Can you explain who invented them and when

they go back to prior to the Romans.

The first was probably a dog who barked when an intruder tried to break in.

bells attached to doors and windows that would ring when they were opened. Others would rely on old tin cans tied together with string and then placed across a pathway. If available, geese made great alarm systems as well.

Please see Wikipedia you will get lot of information there