### Clue: Second attempt to get hydrogen and nitrogen into surprisingly nice poison (10)
### Answer: STRYCHNINE 
 ### Explanation: Definition: poison
 S(abbrev. for "second" in time notation) + TRY(an attempt) **plus**(to get) [ H(symbol for the element hydrogen) **plus**(and) N(symbol for the element nitrogen) ] **contained in**(into) **anagram of**(surprisingly) NICE.