Chamber Where the Boat Will Be
I was surprised to see how quiet Petite France was at night. Most of the people were probably already at the famed Christmas markets so there weren’t a lot of people here. This is good because I won’t have to jostle around with people to get a decent shot of Petite France at night. It is also a great experience to walk along the canal here at Petite France. I noticed that there was still a tourist ferry here and I thought it was strange because it was practically night time so you won’t really see much when you do a river cruise. Anyway, it was still moving and it was approaching the lock.
Boat Entering the Chamber
A lock when used in the context of rivers or canals is sort of an elevator for boats. Think about it, the city of Strasbourg isn’t totally flat which means that the water would be flowing one way, which is downhill. If a boat was to go the other way, there is no way for it to go up. A solution is to control the flow of the river and installing locks. The locks help to maintain the level of water where the locks are. One side of the lock would have a higher water level and the other side would be lower. So how does it help boats move upstream? You can setup to gates where the boat would be going through. The furthest gate would close first keeping the water from flowing into the area where the boat is. The gate behind the boat would close as well. This forms a chamber where the water level can be controlled by filling it up with water.
Boat Moving On After the Chamber Fills Up
At this point the water level where the boat is would be the same as the level from which it entered from. The furthest gate opens letting water in and slowing filling the chamber where the boat is with water. Since this is effectively an enclosed area, the water level would increase, lifting the boat up in the process, thus the elevator analogy. Once the water level of the enclosed area is the same as the level of the water ahead of the boat, the gate fully opens and the boat can proceed. It is a very ingenious solution, and this has been in use for hundreds of years. It is amazing to see it still in use to this day.
[xmlgm {http://www.worldwanderings.net/kml/PetiteFrance.kmz} zoom=19]