Thank you for your response
They are in /var/cache/apt/archives and there are 3700
An example acpid 2.0.4.1 pclos.i586 rpm
thanks
Yes, you can delete them. You can also
avoid their
build up in the future.
In
Synaptic,
Settings --> Preferences --> Files tab, set the second option to
Delete your packages after installation.

To delete those already there, click the
Delete Cached Package Files button.