# Early mechanical/analog computers

I am currently working on a project on early mechanical computers; I understand the basics of how the rotor mechanisms, and whatnot work. However, I need some specific, and preferably diagrams. Most of the sources I've found refer to the broader working of the mechanism (and the implications), would anyone have a source that tackles it more from a engineering perspective, of the mechanism themselves?
Thank you!

Define mechanical computer? I can remember my dad working in upholstery plants and they used a system of punch card on a rotating belt to input information into the loom machines mechanically. As the cards rotated into the machine they would allow the loom needles to either drop out or engage at different intervals. My dad was a "fixer" so his job was to replace damaged card set patterns and make new ones. As I got older I realized that this method could be thought of as a form of computer...the cards representing the data, the punched holes as 0's and 1's like binary code.

https://en.wikipedia.org/wiki/Jacquard_loom

Dembara
Nidum
Gold Member
Search on :

Mechanical analogue computers
Mechanical computing mechanisms

Charles Babbage computer
Tide level calculation machine

Bomb sight computer mechanism
Antikythera mechanism

Cams slides and gears for computing mechanisms
Calculating engines

Define mechanical computer?
Sorry I didn't clarify. It's a large paper, so anything would help, specifically though I am focusing on stuff in the 18th-19th century (and really early 20th). Thank you! Also, that's cool, my father worked with some of the early punch cards also, when working as a professor, though I think that was a bit later (though punch cards were around, I think my dad used them when they were a way of coding, that was read into electronics).

gjonesy
Nidum
Gold Member
Define mechanical computer? I can remember my dad working in upholstery plants and they used a system of punch card on a rotating belt to input information into the loom machines mechanically. As the cards rotated into the machine they would allow the loom needles to either drop out or engage at different intervals. My dad was a "fixer" so his job was to replace damaged card set patterns and make new ones. As I got older I realized that this method could be thought of as a form of computer...the cards representing the data, the punched holes as 0's and 1's like binary code.

Also :

Organs
Sequence controlled machine tools
Programmable numerically controlled machine tools
Code breaking machines

Dembara
Search on :

Mechanical analogue computers
Mechanical computing mechanisms

Charles Babbage computer
Tide level calculation machine

Bomb sight computer mechanism
Antikythera mechanism

Cams slides and gears for computing mechanisms
Calculating engines
Thank you, though I have already tried googling many of those (though I'll try the two I haven't being the bomb sight, and antikythera). Do you know of any specific places, or resources that tend to hold diagrams for them?

Also :

Organs
Sequence controlled machine tools
Programmable numerically controlled machine tools
Code breaking machines
Weren't those in the mid-20th century (I don't recognize what you mean by organs, but the others I recognize)? For the project I am doing I can't use anything after the first world war.

Nidum
Gold Member
Nidum
Gold Member
Organs
Sequence controlled machine tools

Programmable numerically controlled machine tools
Code breaking machines

The first two existed well before the First World War .
The second two evolved mostly from the 1930's onwards

Sorry I didn't clarify.

Its ok, the jacquard (type ) punch card loom was used up until I know of the early 90's. And I remember seeing a documentary on how these simple innovations led to the advancement of early mechanical computing and data entry. So did those old player pianos and music boxes. When you look at these machines you are looking at the great great great grandfather of the modern computer I am using to create this post.

Nidum
Gold Member
You could make your project much more interesting by creating virtual reality models of some of the mechanical computer mechanisms . You could even make them function and demonstrate the calculations evolving .

gneill
Mentor
@Dembara Did you check for patents?

Dembara
Nidum
Gold Member
You could make your project much more interesting by creating virtual reality models of some of the mechanical computer mechanisms . You could even make them function and demonstrate the calculations evolving .
Unfortunately, my project is primarily written (it is actually a history project, but rather open in subject matter), so I don't think that would be possible.

@Dembara Did you check for patents?
Is there any data base that sorts them with dates? I know the US trademark office site, but it gives all of them (and all related laws), and even under mechanical computers, it doesn't give me enough options to practically organize it.

gneill
Mentor
Is there any data base that sorts them with dates? I know the US trademark office site, but it gives all of them (and all related laws), and even under mechanical computers, it doesn't give me enough options to practically organize it.
I'm not aware of such. Which of course doesn't mean it doesn't exist.

You might need to look for survey articles on the history of difference engines to get the dates, then look up the individual patents.

NascentOxygen
Staff Emeritus
Didn't someone in the last year or two start to construct for the first time a computing machine based on the futuristic design drawings of someone from centuries ago? We were told that only now is technology able to support a practical realisation of his vision.

Here's an astronomical calculator from 2000 years ago, built using 30 bronze gears. http://m.livescience.com/1166-scientists-unravel-mystery-ancient-greek-machine.html

Nidum
Gold Member
Last edited:
Dembara
https://www.jlab.org/ir/MITSeries/V27.PDF

An excellent book which contains many line drawings of the actual mechanical computing elements .
I can't seem to see all the info on it (or I am just looking over it), could you give me the name and/or the full citation? Thank you! It looks really useful.

Nidum