Can I change number of command in my histoy file?

Hello, ROOTers.

As ROOT user’s manual tell me,
ROOT stores last 100 commands in .root_hist file.

If it is possibe to change the number of stored commands,
how can I change it ?
I would like to store more last commands.

I use ROOT v3.10.02 with gcc 3.0.4 on IRIX 65.

Thanks