function random_imglink(){
var myimages=new Array()

myimages[1]="img/sundial.jpg"
myimages[2]="img/microscope.jpg"
myimages[3]="img/orrerywright.jpg"
myimages[4]="img/bham.jpg"
myimages[5]="img/telescope.jpg"
myimages[6]="img/thermo.jpg"
myimages[7]="img/leaflet10.jpg"



var ry=Math.floor(Math.random()*myimages.length)
if (ry==0)
ry=1
document.write('<img src="'+myimages[ry]+'" width="218" height="153" />')
}
random_imglink()