WALLPAPER FOR KEYBOARD LAYOUT
The SEMTOG font has been through hundreds of revisions and trials
to boil down the number of necessary elemental symbol characters to 192.
It is done, though there may be occasional updates. The current version is SEMTOG43.ttf
Rather full visual expression of thought is possible with this font.
One standard true type font is all you need.
The most commonly used symbol elements
are on the standard lower and upper case keys,
and the rest are easily typed using the "ALT" key
and typing the four digit numbers on the wallpaper above.