Machine memory and sequential reading

Joseph Jacquard

In 1801 Joseph Marie Jacquard invented what most historians agree was the first machine that operated on the basic principles of the modern digital computer. This machine could access a series of memory devices and produce an output based on the information stored in the memory. The output consisted of a series of colored patterns built line-upon-line on a rectangular field, much like modern computer displays.

The memory consisted of a set of heavy paper cards with holes punched into them. The memory reader was a matrix of dowels that were pressed against the cards. If a dowel encountered a hole, it would pass through carrying a thread with it. This thread would pull a hook that pulled another thread allowing yet another thread to be passed behind it. The machine did this repeatedly weaving threads together forming a pattern on cloth.

Jacquard Loom

This invention, today known as the Jacquard loom, demonstrates three of the fundamentals of the digital computer. These are:

1. the ability to store binary information in a memory device;
2. the ability to read the memory in sequence and;
3. the ability to produce a usable output based on the stored information.

The loom also had a mechanism to automatically develop a visual output by placing a series of various colored pixels in parallel rows. To put it in modern terms, Jacquard developed the first computer memory, the first memory reader, the first output subsystem, and the first color graphic display. The Jacquard loom is comparable to key parts of the video graphic subsystem of modern computers.

The punched cards of a Jacquard Loom

The Jacquard loom was the first machine to read a stored program and produce a useful result based on that program. The principles of the Jacquard loom were soon put to other uses. Two of the most popular were automated music machines and automated water fountain displays.