What is an appropriate time to wait before asking for a second date?

Recently I posted here: http://www.fluther.com/130250/how-many-times-have-you-been-truly-smitten-by-someone/ after a great first date. Now, I am wondering what is the appropriate time to wait to ask for a second date, and so again I am asking my fellow jellies. I do not want to be too eager in pursuing her, as I think there will be plenty of time to get to know each other. But I also don’t want to lose her interest. Do girls “lose interest” if they are not contacted within so many days/weeks, assuming they are interested to begin with?

It’s been almost a weeks time since then with no contact b/w us.