Something weird about one track from the OST

[Subway]

Hi everyone !

First of all I'd like to thank Amanita Design a trillion time for giving me the opportunity to play a REAL game, definitely a one I'll never forget and surely one of the best I've ever played.

I've got a question about the OST (which is simply gorgeous) : I remember that I've fallen in love with the music called "The Glasshouse With Butterfly" while playing the game but as far as I can remember, I heard this track just before entering the glasshouse, on the elevator when you talk to your girlfriend. Unfortunately, I played a second time but this was not that theme but another one. So my question is : Am I crazy, or did someone also hear this track where I heard it (juste before the glasshouse) ?

Thank you for reading and sorry for my English, I'm French 

[ABoretz]

Read Ilsyde's explanation here as to how you can find the piece of music you seek.   

[tomanek]

... and/or download it ('By The Wall') from here, because it's a great song (thank you Tomas, thank you Amanita!)
http://machinarium.net/blog/2009/11/22/free-machinarium-soundtrack-bonus-ep