How to Treat a Jammed Finger - Health Sutra - Duration: 1:54. Health Sutra - Best Health Tips 79,423 views
Brown rat. The brown rat, also referred to as common rat, street rat, sewer rat, Hanover rat, Norway rat, Norwegian rat, or wharf rat (Rattus norvegicus) is one of the best known and most common rats.
A sewer pipe is normally at neutral air pressure compared to the surrounding atmosphere. When a column of waste water flows through a pipe, it compresses air ahead of it in the pipe, creating a positive pressure that must be released so it does not push back on the waste stream and downstream trap water seals.