function nextPage() 
{
thisPage = location.href.substring(location.href.lastIndexOf("/")+1, location.href.indexOf(".html"))
location.href = (parseInt(thisPage) +1) + ".html"
}

function prevPage() 
{
thisPage = location.href.substring(location.href.lastIndexOf("/")+1, location.href.indexOf(".html"))
location.href = (parseInt(thisPage) - 1) + ".html"
}