Did Charles Babbage's Difference Engine use the sautoir carry mechanism from Pascal's calculator?

We know that Blaise Pascal built a mechanical calculator which had a carry mechanism called a sautoir.

You can see a video of it working here, and here.

We know that Charles Babbage wrote a book of log tables.

In doing this, Babbage was inspired to create Log Tables mechanically, leading to his design of the Difference Engine.

My question is: Did Charles Babbage's Difference Engine use the sautoir carry mechanism from Pascal's calculator?

• Based on your research, what would you conclude? – Solar Mike Sep 26 '19 at 5:33

Short answer is no. Longer answer is that the Babbage Difference engine has taken the concept of a sautoir and implemented something much more complicated.

Here we have two wheels representing values in the calculation, and the gear in the middle that adds.

Then to carry numbers up - there was an external device:

Keep in mind that a single number is represented vertically on a column, so the values and the carrying device were replicated vertically.

See also this Counter built by a person who built a Difference Engine built out of Meccano - which implemented its own carry mechanism:

This arm will engage between two of the double brackets on the detent assembly of the adjacent dial and cause it to advance by one unit.”

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