Can't connect to local network using Firefox on IOS

I have a very simple web server on my desk using an ESP8266. It has it's own IP address 10.18.2.3 If I enter this url on Firefox on Android it works just great. However when I enter the same url of Firefox on IOS is does nothing and says "No Internet Connection". I already know there is no internet connection and I do not want one. I just want to have Firefox work the same as it does on Android. What settings do I need to change in IOS to make this work ? I am also curious why it shouldn't work on IOS in the first place too. Thanks Alan