<!-- For javascript form control

// Array Function 

function makeArray() {
var args = makeArray.arguments;

    for (var i = 0; i < args.length; i++) {
    this[i] = args[i];
    }
this.length = args.length;
}

// This array holds the descriptions and names of the pages.

var pages = new makeArray("----------MENU----------",
"-----------------",
"Introduction",
"How Many Bonds per Atom?",
"Carbon Compounds",
"Double and Triple Bonds",
"Diamond and Graphite",
"Nitrogen and Ammonia",
"Oxygen and Water",
"The Interaction of Ammonia and Water; Bases",
"Fluorine and Hydrofluoric Acid",
"Summary",
"Questions and Problems",
"-----------------",
"go to the Virtual Laboratory");


// This array hold the URLs of the pages.

var urls = new makeArray("",
"",
"intro1.htm",
"bondsperatom1.htm",
"carbon1.htm",
"doubleandtriple1.htm",
"diamond1.htm",
"Nitrogen1.htm",
"Oxygen1.htm",
"Ammonia1.htm",
"Fluorine1.htm",
"Summary1.htm",
"Questions1.htm",
"",
"http://www.chem.ox.ac.uk/vrchemistry");






// This function determines which page is selected and goes to it.

function goPage(form) {
i = form.menu.selectedIndex;            
    if (i != 0) {
    window.location.href = urls[i];  
    }
}
//-->