The perfect murder??????!

The perfect murder??????

Edward carefully plotted the murder of his wife. One winter's day he strangled her in the bedroom, then faked a burglary. He ransacked the house, scattered possessions and broke through the patio doors. He set the burglar alarm downstairs before driving to the local golf course to establish his alibi. Two hours later, when Edward was in the middle of his golf course with three colleagues, the burglar alarm went off and the police were alerted. They found the house apparently broken in to and the wife strangled. No animals or electrical devices were found which could have set off the alarm before killing the poor woman. Edward was never arrested or charged. The police inspector long suspected Edward, but there was one question which he could not fathom: How did he get the burglar alarm to go off so conveniently? Can you work it out?????

3 weeks ago
i will give a clue in a little while

3 weeks ago
big money is the closest so far, but what fell and how???

3 weeks ago
it wasn't snowing

3 weeks ago
how did he get something to fall????

3 weeks ago
something had to have moved without anybody touching or doing anything?????

was a ruler on the side of the counter with a ice cube on it and when it melted the ruler fell and set off the alarm. Idk if that is right but maybe something bigger than a ruler or something, maybe 2 rulers????