The melancholy of it! As if old Euclid had stood up on his hind legs and swallowed prussic acid.

它演奏的调子是那么悲哀，似乎老欧几里得用后腿站着吞下了氢氰酸。

The bitter almond contains amygdalin. Acid or enzyme can decompose amygdalin to prussic acid and benzaldehyde. Prussic acid is a poisonous substance.

苦杏仁含有苦杏仁甙，它在酸或酶的作用下，可以分解产生氢氰酸和苯甲醛，氢氰酸剧毒。