function check_form1() {

	var error_msg = '';

	if( document.form1.name.value == '' ||  document.form1.name.value == ' ' ) {
		error_msg += '\nYou must enter your name;';
	}
	
	if( document.form1.tel.value == '' ||  document.form1.tel.value == ' ' ) {
	error_msg += '\nYou must enter your telephone number;';
	}
	
	if( document.form1.email.value == '' ||  document.form1.email.value == ' ' ) {
	error_msg += '\nYou must enter your e-mail address;';
	}

	if( document.form1.address.value == '' ||  document.form1.address.value == ' ' ) {
	error_msg += '\nYou must enter your address;';
	}
	
	if( document.form1.postcode.value == '' ||  document.form1.postcode.value == ' ' ) {
	error_msg += '\nYou must enter your postcode;';
	}

	if( error_msg == '' ) {
		return true;
	} else {
		alert( 'You can not proceed for the following reasons:\n' + error_msg );
		return false;
	}

}