function showLayer(number)
        {
            // Hide last displayed form
            
            these_forms = new Array();
            these_forms[0] = 1;
            these_forms[1] = 2;
            these_forms[2] = 3;
            these_forms[3] = 4;
            
            for (var i = 0; i < these_forms.length; i++)
            {
                if (these_forms[i] != number)
                {
                    if (document.getElementById("idForm" + these_forms[i]).style.display == 'block')
                    
                        document.getElementById("idForm" + these_forms[i]).style.display = 'none'
                    
                }
            }
            
            // Show selected form
            
            document.getElementById("idForm" + number).style.display = 'block';            
        }