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# Adventure in London: The Cogs of Big Ben

Teyus walked over to the cogs and saw each one had a strange name, that referred to different units of time (hours, minutes, seconds). While the rest of the cogs were slowly trying to churn, groaning and barely moving, the little cog, called the ‘escapement’ which measured the seconds, had stopped.

“An act of espionage!” shouted Mr. Bondo.

Teyus studied the cogs and looked underneath the machinery. He flipped open his multi-utility knife and gently unclogged something from the bottom. Very carefully, he went under the cogs and removed a small sparrow’s nest that had gotten stuck below the machine!

“Bravo!” said Mr. Bondo. “No doubt put there by our nation’s enemies!”

Mira and Teyus just smiled.

But the problem was still not fixed.

The pendulum was too tilted! There was no way it could move at the correct rate, Mira had been studying the pendulum. There were pennies put on top of it to stabilize it. Over the last 100 years, the watch-keepers had been using pennies to balance the weight of the pendulum. “These must be off balance”, she thought.

There was only two minutes left before the pendulum had to strike. She mentally calculated the weights of the coins on the pendulum and the different angles they were at.

British pennies weighed 3.56 grams each.

A five pence coin was 3.25 grams.

And the single one pound coin was 9.50 grams.

They were about four and a half grams short.
Searching in her pockets, she found a single coin, a Canadian quarter. It felt like the correct weight but she couldn’t be sure.  There was no option but to try.

Very carefully, she studied the angles of the other coins and delicately placed the Canadian quarter with the image of the caribou on one side, and the Queen on the other, on top of the pendulum. She then stepped back, holding her breath.

Everyone stopped and looked at the pendulum.  Would they be able to save Millennial Celebrations?

Just then, with a loud bang, Big Ben rang on time!  It was so loud that Mira and Teyus practically jumped up in fright.

In the commotion, they had forgotten about Hari.  Where was he?  Teyus looked around the bell tower and he was nowhere to be seen!

“Oh No! Not only was he lost geographically and in a different time period, he’s also lost in the largest city in Europe! How are we ever going to find him?” wondered Mira.

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