function validate()
            {
                var doc = document.contact_form;
                if(doc.name.value == '')
                {
                    alert("enter the name");
                    doc.name.focus();
                    return false;
                }
                if(doc.email.value == '')
                {
                    alert("enter the email");
                    doc.name.focus();
                    return false;
                }
                if(doc.message.value == '')
                {
                    alert("enter the message");
                    doc.message.focus();
                    return false;
                }
                return  true;
            }