| AQUAFORTIS | Water on top of castle is nitric acid! (10) |
| CASTELLAN | Governor of castle is able to embrace feminine star (9) |
| ASWELL | A heaving of water on top (2,4) |
| INTRINSIC | Nitrogen is nitric form that is essential (9) |
| ARISTOCRAT | Lady, perhaps, noticed a knight returning to top of castle to overturn dark, flammable substance |
| CROFT | Scottish smallholding - top of castle attached to sort of fort! (5) |
| NICK | Arrest family climbing round top of castle (4) |
| GOALKEEPER | Gaoler running around castle is last line of defence |
| DRAWBRIDGE | This admission to castle is a let-down (10) |
| MAIDENHEAD | Royal Borough of Windsor & ___ (Where Queen Elizabeth's weekend home Windsor Castle is located in England) |
| KEEPINMIND | Don't forget castle is popular with wits (4,2,4) |
| WESTSUSSEX | English county in which Arundel Castle is located (4,6) |
| AMMONIA | Colourless pungent gas composed of one atom of nitrogen bonded to three atoms of hydrogen, chiefly used in the manufacture of fertilisers and nitric acid (7) |
| TARTARIC | The fierce fellow, I see, is acid! (8) |
| BURN | Running water can act like acid! (4) |
| NITRATE | What, in chemistry, is a salt of nitric acid (7) |
| REGIA | Mixture of hydrochloric acid and nitric acid used for dissolving gold (4,5) |
| AQUA | Mixture of nitric acid and hydrochloric acid (4,5) |
| GLAMIS | This castle is on a sort of rock (6) |
| COMEDIANS | Funny men, funny men. So acid! |
