20   uint8 bits_per_sample;
 
   42   SND_03_FACTORY_WHISTLE,
 
   44   SND_05_TRAIN_THROUGH_TUNNEL,
 
   47   SND_08_PLANE_TAKE_OFF,
 
   50   SND_0B_MINING_MACHINERY,
 
   51   SND_0C_ELECTRIC_SPARK,
 
   53   SND_0E_LEVEL_CROSSING,
 
   54   SND_0F_VEHICLE_BREAKDOWN,
 
   55   SND_10_TRAIN_BREAKDOWN,
 
   64   SND_19_BUS_START_PULL_AWAY,
 
   65   SND_1A_BUS_START_PULL_AWAY_WITH_HORN,
 
   78   SND_27_BLACKSMITH_ANVIL,
 
   83   SND_2A_EXTRACT_AND_POP,
 
   87   SND_2E_EXTRACT_AND_POP,
 
   94   SND_35_COMEDY_BREAKDOWN,
 
   96   SND_37_BALLOON_SQUEAK,
 
   99   SND_3A_COMEDY_BREAKDOWN_2,
 
  102   SND_3D_ANOTHER_JET_OVERHEAD,
 
  105   SND_40_COMEDY_CAR_START_AND_PULL_AWAY,
 
  110   SND_45_PLANE_CRASHING,
 
  111   SND_46_PLANE_ENGINE_SPUTTERING,
 
  120 typedef uint16 SoundID;
 
  122 static const SoundID INVALID_SOUND = 0xFFFF;