It's not until after she dies that Scout and Jem get a sense of what's going on behind the drool and venom: Mrs. Dubose is a morphine addict who had vowed to go clean before she died, and enlisted Jem and Scout (without their knowledge) to keep her off the stuff for longer and longer periods of time.
http://lungsounds.net/rales-lung-sounds/ - Rales lung sounds are small rattling noises heard around the lung. This happens when air exposes closed air spaces. Rales can be shown as wet, dry and coarse.
Breath Sounds - Crackles. You are now listening to a typical example of breath sounds with scattered wet crackles. Also known as rales, these abnormal breath sounds are usually caused by excessive fluid within the airways. This fluid could be due to an exudate, as in pneumonia or other infections of the lung, or a transudate, as in congestive heart failure.