'on the contrary' or 'to the contrary'

[enydia]

Hello, Teachers.

I just learnt two phrases: 'on the contrary' and 'to the contrary'. I know there must be something different between them, but I can not pin it down.

For example, in the following sentence, can I substitute 'on the contrary' for 'to the contrary'?
I will come on Monday unless you write to the contrary.

It would be very nice if I could have your explanation or advice.

Thanks in advance.

Enydia

[Soup]

From to the contrary - definition of to the contrary by the Free Online Dictionary, Thesaurus and Encyclopedia.

on the contrary
In opposition to what has been stated or what is expected.
Ex: I'm not sick; on the contrary, I'm in the peak of health.


to the contrary
To the opposite effect from what has been stated or what is expected.
Ex: Despite what you say to the contary, this contract is fair.

[Soup]

See also here http://www.usingenglish.com/forum/as...-contrary.html