var num=1
img1 = new Image ()
img1.src = "pic_01.jpg"
img2 = new Image ()
img2.src = "pic_02.jpg"
img3 = new Image ()
img3.src = "pic_03.jpg"
img4 = new Image ()
img4.src = "pic_04.jpg"
img5 = new Image ()
img5.src = "pic_05.jpg"
img6 = new Image ()
img6.src = "pic_06.jpg" 
img7 = new Image ()
img7.src = "pic_07.jpg" 
img8 = new Image ()
img8.src = "pic_08.jpg" 
img9 = new Image ()
img9.src = "pic_09.jpg" 
img10 = new Image ()
img10.src = "pic_10.jpg" 

function slideshowUp()
{
num=num+1
if (num==11)
{num=1}
document.photogallery.src=eval("img"+num+".src")
}

function slideshowBack()
{
num=num-1
if (num==0)
{num=10}
document.photogallery.src=eval("img"+num+".src")
}