var imageIndex = "image1";
    
    function changePhoto() {	
    
      if (imageIndex == "image1") {
          document.images[1].src = "Images/home/image2.jpg";
          imageIndex = "image2"; 
      } else if (imageIndex == "image2") {
          document.images[1].src = "Images/home/image3.jpg";
          imageIndex = "image3"; 
      } else if (imageIndex == "image3") {
          document.images[1].src = "Images/home/image4.jpg";
          imageIndex = "image4"; 
      } else if (imageIndex == "image4") {
          document.images[1].src = "Images/home/image5.jpg";
          imageIndex = "image5"; 
      } else if (imageIndex == "image5") {
          document.images[1].src = "Images/home/image6.jpg";
          imageIndex = "image6"; 
      } else if (imageIndex == "image6") {
          document.images[1].src = "Images/home/image7.jpg";
          imageIndex = "image7"; 
      } else if (imageIndex == "image7") {
          document.images[1].src = "Images/home/image8.jpg";
          imageIndex = "image8"; 
      } else if (imageIndex == "image8") {
          document.images[1].src = "Images/home/image9.jpg";
          imageIndex = "image9"; 
      } else if (imageIndex == "image9") {
          document.images[1].src = "Images/home/image10.jpg";
          imageIndex = "image10"; 
      } else if (imageIndex == "image10") {
          document.images[1].src = "Images/home/image11.jpg";
          imageIndex = "image11"; 
      } else if (imageIndex == "image11") {
          document.images[1].src = "Images/home/image12.jpg";
          imageIndex = "image12"; 
      } else if (imageIndex == "image12") {
          document.images[1].src = "Images/home/image13.jpg";
          imageIndex = "image13"; 
      } else if (imageIndex == "image13") {
          document.images[1].src = "Images/home/image14.jpg";
          imageIndex = "image14"; 
      } else if (imageIndex == "image14") {
          document.images[1].src = "Images/home/image15.jpg";
          imageIndex = "image15"; 
      } else if (imageIndex == "image15") {
          document.images[1].src = "Images/home/image16.jpg";
          imageIndex = "image16"; 
      } else if (imageIndex == "image16") {
          document.images[1].src = "Images/home/image17.jpg";
          imageIndex = "image17"; 
      } else if (imageIndex == "image17") {
          document.images[1].src = "Images/home/image18.jpg";
          imageIndex = "image18"; 
      } else if (imageIndex == "image18") {
          document.images[1].src = "Images/home/image19.jpg";
          imageIndex = "image19"; 
      } else if (imageIndex == "image19") {
          document.images[1].src = "Images/home/image1.jpg";
          imageIndex = "image1"; 
      }
                  
    }