When Motif initialises the application it looks for a special file in your HOME directory: .Xdefaults.
This file contains directives that can reset any resource using the following method:
push.Push_me.width or push.Push_me.height
NOTE: the XmN has been dropped from the resource name.
push.Push_me.width: 200 push.Push_me.height: 300
where 200 and 300 are the widget dimensions.
The advantage of this method is that we do not have to alter and recompile our program to get different sized widgets.