function hide(id) {

  document.getElementById(id).style.backgroundImage = "none";

}

function display(image, id) {
  
  document.getElementById(id).style.backgroundImage = 'url(' +image+ ')';

}

function preloader() {

  img1 = new Image();
  img1.src = "images/logos/cumbria-community-foundation.gif";
  
  img2 = new Image();
  img2.src = "images/logos/west-coast-railways.gif";
  
  img3 = new Image();
  img3.src = "images/logos/environment-agency.gif";
  
  img4 = new Image();
  img4.src = "images/logos/betafence.gif";
  
  img5 = new Image();
  img5.src = "images/logos/wild-trout-trust.gif";
  
  img6 = new Image();
  img6.src = "images/logos/sbj.gif";
  
  img7 = new Image();
  img7.src = "images/logos/national-grid.gif";
  
  img8 = new Image();
  img8.src = "images/logos/yorkshire-dales-millennium-trust.gif";
  
  img9 = new Image();
  img9.src = "images/logos/rivers-trust.gif";
  
  img10 = new Image();
  img10.src = "images/logos/united-utilities.gif";
  
  img11 = new Image();
  img11.src = "images/logos/forest-of-bowland.gif";
  
  img12 = new Image();
  img12.src = "images/logos/sita.gif";
  
  img13 = new Image();
  img13.src = "images/logos/hadfield-charitable-trust.gif";
  
  img14 = new Image();
  img14.src = "images/logos/lancaster-city-council.gif";
  
  img15 = new Image();
  img15.src = "images/logos/aca.gif";
  
  img16 = new Image();
  img16.src = "images/logos/cumbria-biodiversity-partnership.gif";
  
  img17 = new Image();
  img17.src = "images/logos/entrust.gif";
  
  img18 = new Image();
  img18.src = "images/logos/enventure.gif";
  
  img19 = new Image();
  img19.src = "images/logos/defra.gif";
  
  img20 = new Image();
  img20.src = "images/logos/esmee-fairbairn-foundation.gif";
  
  img21 = new Image();
  img21.src = "images/logos/sws-uk.gif";
  
  img22 = new Image();
  img22.src = "images/logos/lancashire-environmental-fund.gif";
  
  img23 = new Image();
  img23.src = "images/logos/cumbria-waste-management.gif";
  
  img24 = new Image();
  img24.src = "images/logos/websiteuk.jpg";
  
  img25 = new Image();
  img25.src = "images/logos/world-owl-trust.gif";
  
  btn = new Image();
  btn.src = "images/send-email-on.jpg";

}