Here's the script...

function addline(daline) {
    var dv = document.createElement("div");
    var text = document.createTextNode(daline);
    dv.appendChild(text);
    //insert in beginning of doc
    document.body.insertBefore(dv, document.body.firstChild)
}

and a form to initiate it...

<form>
<input type="button" value="insert text" onclick="addline('when in the course of human events...'); return(false);">
</form>