function SwapImage(PageNumber, ImageNumber)
{
		//Updates image and text caption
		//Assumes image id = MainImage
		// and caption text span id = CaptionText
	
	
		// Set image captions
	
		//First number = Page Number
		//Second number = Image Number
		
		var ImgPages = new Array(4,10);
		
		//Page 1 (blank)
		ImgPages[1,1] = "leave blank";
		ImgPages[1,2] = "leave blank";
		ImgPages[1,3] = "leave blank";
		
		//Page 1 (Jo)
		ImgPages[2,1] = "Image caption Jo 1";
		ImgPages[2,2] = "Image caption Jo 2";
		ImgPages[2,3] = "Image caption Jo 3";
		ImgPages[2,4] = "Image caption Jo 4";
		ImgPages[2,5] = "Image caption Jo 5";
		ImgPages[2,6] = "Image caption Jo 6";
		ImgPages[2,7] = "Image caption Jo 7";
		
		//Page 2 (Alison)
		ImgPages[3,1] = "Image captioning Alison 1";
		ImgPages[3,2] = "Image caption Alison 2";
		ImgPages[3,3] = "Image captioning Alison 3";
		ImgPages[3,4] = "Image caption Alison 4";
		ImgPages[3,5] = "Image captioning Alison 5";
		ImgPages[3,6] = "Image caption Alison 6";
		ImgPages[3,7] = "Image captioning Alison 7";
		
		
		
		// Set Image Path
		var NewImagePath = "img/" + PageNumber + "/" + ImageNumber + ".jpg";
				
		//Update image
		document.getElementById("MainImage").src = NewImagePath;
		
		//Updates text
		//document.getElementById("CaptionText").innerHTML = ImgPages[PageNumber,ImageNumber];
}