<!-- 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(" -- Jump to --",
"- - - - - - - - - - - - -",
"Introduction",
"Electrons, Nuclei, And Atomic Number",
"Isotopes of Hydrogen",
"Isotopes of Helium",
"Isotopes and Observed Atomic Weights",
"Bonds Between Atoms",
"Electron Shells",
"Molecules, Molecular Weight, And Moles",
"Measuring Moles; The Gas Laws",
"Gas Molecules And Absolute Zero",
"The Ideal Gas Law",
"A Chemical World In Miniature: A Summary",
"- - - - - - - - - - - - -",
"Questions",
"Problems",
"- - - - - - - - - - - - -",
"Another Chapter..?");


// This array hold the URLs of the pages.

var urls = new makeArray("",
"",
"page01.htm",
"page02.htm",
"page06.htm",
"page09.htm",
"page12.htm",
"page14.htm",
"page19.htm",
"page21.htm",
"page28.htm",
"page36.htm",
"page40.htm",
"page45.htm",
"",
"ques01.htm",
"prob01.htm",
"",
"http://www.chem.ox.ac.uk/vrchemistry/foundation.html");






// 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];  
    }
}
//-->