| Answer | Crossword Clue |
|---|---|
| aqueducts | AQUEDUCT, a pipe or channel for conveying water |
| aqueduct | a pipe or channel for conveying water |
| flue | pipe for conveying flame and hot gases around or through water in a steam boiler |
| flues | pipe for conveying flame and hot gases around or through water in a steam boiler |
| penstocks | A channel for conveying water to a waterwheel or turbine |
| penstock | A channel for conveying water to a waterwheel or turbine |
