| Answer | Crossword Clue |
|---|---|
| TEN | Basis of logarithms. |
| TEN | Basis of logarithms |
| NAPIER | Inventor of logarithms. |
| NEPER | Father of logarithms |
| NAPIER | Inventor of logarithms |
| NAPIER | Scottish inventor of logarithms (1550-1617). |
| EULER | Mathematician who introduced the symbol e for the base of natural logarithms |
