var tgs = new Array('div');
var go = new Array( '10px','12px','14px','16px' );
var doc = 0;

function zoom( object,inc ) {
if (!document.getElementById) return
var d = document,all = null,plus = doc,i,j,div;

plus += inc;
if ( plus < 0 ) plus = 0;
if ( plus > 3 ) plus = 3;
doc = plus;

if ( !( all = d.getElementById( object ) ) ) all = d.getElementsByTagName( object )[ 0 ];

all.style.fontSize = go[ plus ];

for ( i = 0 ; i < tgs.length ; i++ ) {
div = all.getElementsByTagName( tgs[ i ] );
for ( j = 0 ; j < div.length ; j++ ) div[ j ].style.fontSize = go[ plus ];
}
}