if (document.images){
// main nav rollovers
 our_history_on = new Image(); our_history_on.src = "images/buttons/our_history_on.gif";
 our_history_off = new Image();our_history_off.src = "images/buttons/our_history_off.gif";
 our_team_on = new Image();our_team_on.src = "images/buttons/our_team_on.gif";
 our_team_off = new Image();our_team_off.src = "images/buttons/our_team_off.gif";
 why_us_on = new Image(); why_us_on.src = "images/buttons/why_us_on.gif";
 why_us_off = new Image(); why_us_off.src = "images/buttons/why_us_off.gif";
 our_culture_on = new Image(); our_culture_on.src = "images/buttons/our_culture_on.gif";
 our_culture_off = new Image(); our_culture_off.src = "images/buttons/our_culture_off.gif";
}