var mess = new Array(
'<img src="http://www.green-space.org.uk/Images/Randomimages/1.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/2.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/3.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/4.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/5.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/6.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/7.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/8.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/9.jpg">',
'<img src="http://www.green-space.org.uk/Images/Randomimages/10.jpg">');
var max = mess.length;
var num = Math.floor((Math.random() * max));
document.writeln(mess[num]);