Why were glowworms useful to soldiers

Glowworms (more specifically European glowworms) were used in jars there were thousands were used to help soldiers and officers study maps read letters and read intelligence reports. They emit light through bioluminescence  Just  10 glowworms can have the same illumination as a modern roadway light.  

So in short: They were used for lighting

you can only change it if your real name or personal information was in it. and if so you would need to contact them directly with a username change request.

a macro is a tool that allows you to automate tasks and add functionality to your forms, reports, and controls. for example, if you add a command button to a form, you associate the button's onclick event to a macro, and the macro contains the commands that you want the button to perform each time it is clicked.