function date (form){
var Serial=form.inputbox.value;
if(Serial<=0)
	{Message="That was an invalid serial number";Year="";}
else{Message="Your Henry rifle was manufactured in ";
if(Serial<=270)
	{Year=1860;}
else{
if(Serial<=300)
	{Year=1861;}
else{
if(Serial<=1300)
	{Year=1862;}
else{
if(Serial<=4000)
	{Year=1863;}
else{
if(Serial<=8000)
	{Year=1864;}
else{
if(Serial<=12000)
	{Year=1865;}
else{
if(Serial<=14000)
	{Year=1866;}
else{Message="That was an invalid serial number";Year="";}
}}}}}}}
alert (Message + Year+".");
}