Cannot install over git

Hello,

taking your description about installation leads to an error:

git clone git://github.com/glennhickey/progressiveCactus.git
Cloning into 'progressiveCactus'...
fatal: unable to connect to github.com:
github.com[0: 140.82.121.4]: errno=Connection timed out

I tried it several times - at home and at institute...

What could be wrong?