| Answer | Crossword Clue |
|---|---|
| ARGON | Gas used in incandescent lamps |
| ARGON | Gas in incandescent lamps |
| ARGON | Gas in incandescent lamps, perhaps |
| YTTRIA | White powder used in incandescent gas |
| NEON | Gas used in lamps |
| XENON | Gas used in arc lamps |
| XENON | Gas used in flash lamps |
