Crime scene: 162 mystery solving puzzles to find out who the murderer is

Chapter 17 The Death of the Rich Merchant
A rich businessman celebrated his birthday at home, and the whole family got together to celebrate.The family raised their glasses to congratulate him.But the rich businessman died of poisoning as soon as he took a sip of wine.Later, after police investigation, it was found that:
His wife, younger brother, son, daughter, and maid were dining at the same table with him.His wife has an adulterer outside, and has always wanted to be with the adulterer forever.

His younger brother is also greedy for his sister-in-law's beauty, and he wants to get her, and he also wants to take over the family business from his elder brother.

The son of a wealthy businessman eats, drinks, prostitutes and gambles outside, and owes half of his father's property in debt to others, so he is pushed hard by his creditors.

His daughter fell in love with a poor man, and the rich businessman firmly opposed their association, saying that if he was around for a day, his daughter would never want to be with that poor man.

That maid's whole family was killed by a rich businessman alone. She came to the rich businessman as a servant just to wait for an opportunity to avenge her.

From this, it can be seen that everyone present at the time had a motive for killing.

In addition, according to the evidence obtained by the police, it is known that the wine in his wine glass contained highly toxic potassium cyanide, and his daughter's wine also contained it, while the wine of the others was non-toxic, and the rest of the wine in the bottle was also non-toxic. .Of course, you must be wondering why his daughter was not poisoned.That's because they were drinking and talking at the time, not at the same time, and his daughter and wife found out that something had happened before they had time to drink.

The police inquired about the situation at the time: the maid cleaned and placed the wine glasses, and the daughter poured the wine. Before drinking, the younger brother sitting on the left of the rich businessman mistakenly took his wine glass, but was reminded by the sister-in-law sitting on the right of the rich businessman. , and she stretched out her hand to take it back, because the two hands collided, the wine in the wine glass splashed on the ground, the maid hurried to clean up the wine on the ground, the son saw that there was not much wine left in the father's wine glass, and gave it He fills up.Who is the murderer?
[Answer] His daughter.

First of all, the rich businessman's wife, younger brother, and son have no chance of poisoning his daughter's wine, so they can be ruled out.The maid has the opportunity to poison his daughter's wine, but since she wants to take revenge, she has two purposes: either kill the rich businessman alone, without hurting the innocent; Kill their father and daughter.

The method is this: she painted potassium cyanide on one side of the mouth of the wine bottle in advance, and when she poured wine for her father and herself, she poured it from the poisoned side, but when she poured it for others, she poured it from the non-toxic side.

Why did she poison her own wine? The direct reaction of doing this is that she is also the target of being killed. Anyway, she can't drink it herself, but she did it to cover up.

(End of this chapter)