<!--
function validate(form){
  var errmsg = "";

  if(!form.sname.value)
  {
    if(!errmsg)
      form.sname.focus();
    errmsg += "\n -  your surname";
  }
  if(!checkUKTelephone(form.tel.value))
  {
    if(!errmsg)
      form.tel.focus();
    errmsg += "\n -  a valid UK phone number";
  }
  if(!form.email.value.match(/\b(^(\S+@).+((\.com)|(\.net)|(\.edu)|(\.mil)|(\.gov)|(\.org)|(\..{2,2}))$)\b/gi))
  {
    if(!errmsg)
      form.email.focus();
    errmsg += "\n -  a valid email address";
  }

  if(errmsg.length)
  {
    errmsg = "Please provide" + errmsg;
    alert(errmsg);
    return false;
  }

  if(!(form.enquiry.value)){
    return confirm("You haven't left a message.\n Do you want to continue?");
  }

  return true;
}

//*******************************************
function checkUKTelephone (telephoneNumber) {
//*******************************************
  var telnum;
  // Convert into a string and check that we were provided with a number
  telnum = telephoneNumber + " ";
  if (telnum.length == 1)  {
     telNumberErrorNo = 1;
     return false
  }
  telnum = telnum.substring(0, telnum.length - 1);

  // Don't allow country codes to be included (assumes a leading "+")
  exp = /^(\+)[\s]*(.*)$/;
  if (exp.test(telnum) == true) {
     telNumberErrorNo = 2;
     return false;
  }

  // Remove spaces from the telephone number to help validation
  while (telnum.indexOf(" ")!= -1)  {
    telnum = telnum.slice (0,telnum.indexOf(" ")) + telnum.slice (telnum.indexOf(" ")+1)
  }

  // Remove hyphens from the telephone number to help validation
  while (telnum.indexOf("-")!= -1)  {
    telnum = telnum.slice (0,telnum.indexOf("-")) + telnum.slice (telnum.indexOf("-")+1)
  }

  // Now check that all the characters are digits
  exp = /^[0-9]{10,11}$/
  if (exp.test(telnum) != true) {
     telNumberErrorNo = 3;
     return false;
  }

  // Now check that the first digit is 0
  exp = /^0[0-9]{9,10}$/
  if (exp.test(telnum) != true) {
     telNumberErrorNo = 4;
     return false;
  }

  // Now check that the telephone number is appropriate.
  exp = /^(01|02|05|070|077|078|079)[0-9]+$/;
  if (exp.test(telnum) != true) {
     telNumberErrorNo = 5;
     return false;
  }

  // Seems to be valid - return the stripped telehone number

  return telephoneNumber;
}

function changeHunits(form){
  if(form.h_units.value == 'cm'){
    form.height.value = Math.ceil(2.54 * ((form.height.value * 12) + (form.inches.value * 1)));
    form.inches.style.visibility = 'hidden';
    document.getElementById("inches_l").style.visibility = 'hidden';
  }
  else{
    vCm = form.height.value;
    form.height.value = Div((vCm / 2.54), 12);
    form.inches.value = Mod((vCm / 2.54), 12);
    form.inches.style.visibility = 'visible';
    document.getElementById("inches_l").style.visibility = 'visible';
  }
}

function changeWunits(form){
  if(form.w_units.value == 'kg'){
    form.weight.value = Math.ceil(((form.weight.value * 14) + (form.pounds.value * 1))/2.2);
    form.pounds.style.visibility = 'hidden';
    document.getElementById("pounds_l").style.visibility = 'hidden';
  }
  else{
    vKg = form.weight.value;
    form.weight.value = Div((vKg * 2.2), 14);
    form.pounds.value = Mod((vKg * 2.2), 14);
    form.pounds.style.visibility = 'visible';
    document.getElementById("pounds_l").style.visibility = 'visible';
  }
}

function Mod(X, Y) { return Math.floor(X) - Math.floor(X/Y)*Y }
function Div(X, Y) { return Math.floor(X/Y) }
//-->