Thousand bottles of Wine

A twist on the well known puzzle:

A king has stocked 1000 bottles of wine in the wine cellar for a big party the day after tomorrow.
The chief of guards brings bad news at noon: an assassin belonging to a fanatic religious sect has been caught in the wine cellar with a vial half-full of poison. Interrogation reveals that she has put an undetectable, very deadly poison in a single wine bottle. The poison causes certain death in 20 to 22 hours, without prior symptoms, and that too with a just a drop of the poisoned wine.

To balance her karma, the assassin has also put an antidote to the poison in another wine bottle. The antidote is even more powerful: a single drop from the antidote-containing wine bottle will neutralize the effects of drinking even the whole poisoned wine bottle.

Mixing all the wines is not an option because they are of different types.

How many prisoners on death row does the chief of guards need to use determine which wine bottle has the poison?

Clock Puzzle

Which is the better clock: one that loses/gains 5 to 10 minutes a day, or one that is absolutely accurate 26 times a day?

Hint: there is an aphorism

Addendum: The above question is for a 24-hour clock. For a 12-hour clock, the puzzle becomes:

Which is the better (12-hour analog) clock: one that loses/gains 5 to 10 minutes a day, or one that is absolutely accurate 21 times a day?

Hint: the question was asked in September.