Today is all about the famous Peterborough Lift Lock which is effectively two big bathtubs. They are connected by a piston. They fill the bathtub at the top (left in the picture below) with 12″ more water than the lower one, plus the boats going down. The weight difference imbalances the two bathtubs and forces the piston down on the upper bathtub side and therefore the piston up, on the lower bathtub and it carrying the boats up. There is no power used to transition the chambers, only the weight imbalance. Designed in 1896 (yes the 1800s) and completed in 1904.

This is a picture of the structured of the chambers from underneath. They have to support a great deal of weight. You can see the single supporting black piston on the right.

Thanks to Grace on a sailboat that Mark and Debra befriended here is Cherish going up. First Cherish entering the lower chamber (bathtub) in this case on the right-hand side.  That is Mark standing on the upper deck (the sky lounge) in the blue shirt.

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They close the “tailgate” on the bathtub, like a normal truck pick-up tailgate, seen here as the brown/black metal end on the bathtub.

Cherish as the pistons are forced to equilibrium caring the boat filled cambers on the way.

Cherish near the top.

Debra enjoying the ride up and Mark looking out the stern of Cherish, over the edge of the end of the chamber.

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Stepanie’s picture, out the end of the bathtub. For scale, you can see the back end of the 11′ dinghy Fitz compared to the long way down.

Here you can see the 6″ differential between the canal and what was the lower chamber.  They then lower the tailgate at the front of the bathtub. The water rushing in equalizes to the canal height and now make what was the lower chamber, the upper chamber heavier with 12″ more water then the lower chamber and off it goes again.

Exiting the upper chamber looking backward. This is what it looks likes entering the upper chamber. That is, driving off the end of the earth as you will see in the next lock like this coming up in a few weeks.

On the left, these Europeans rented a canoe to experience the locks. Almost free and very exciting! On the right for some scale, you can barely see their small canoe by another retired rail bridge. For those of you who have not canoed recently, they are very tipping and very hard to empty once tipped and swamped.

Yet another decommissioned rail bridge

More of Stephanie’s lock wall art.

We started the day at lock #21 and tied up to end the day on the blue line of lock #26.

This is the damn beside Lock #26.

Stephanie and Currie went grocery shopping at Foodland and then off to use the Wifi for uploading blog pictures at the Library. This is locking back on the lock.

Looking across the lock.

Courtesy of Bing Maps