Posted by: Wayne Robinson | May 7, 2010

A Seventeenth Century Take on Flowcharts

For the uninitiated or cave-dwellers, flowcharts are a type of diagram representing a process, showing the steps and their order by connecting these with arrows.

Most sources claim the flowchart was either first used in 1921, or if they insist on the modern structured flowcharts that evolved from the Nassi-Shneiderman Diagrams, first published in 1972. Many modern flowchart users wouldn’t recognise or even understand how to use these early forms.

Nassi-Shneiderman diagram on From Wikipedia.
Nassi-Shneiderman diagram on From Wikipedia

Most authors say flowcharts were exclusively used for programming, while others permit other engineering applications as well.

Here’s an example of one that maps a process, but isn’t programming or engineering. You could probably argue that most people who would use it were in the ICT or engineering field, but the point is that almost everyone looking at it can follow what it is showing.

The Ultimate Gaming Cycle Flowchart

The problem with all this posturing (some people take themselves very seriously), and the reason for this post is that I’ve recently seen a few that are older. Much, much older.

Here’s the first one I saw, from Toxophilus by Roger Ascham written in 1545. The flowchart is the table of contents for the second book, appearing in page XX.  My copy is from a 1904 reprint of the first edition, and is faithful to the original.

Ascham 1545

No doubt some readers are going to say that this is simply a typesetting convention, a hang-over from when all type had to be individually hand cut and the convention was an easy way to avoid repetition. Let’s have a closer look and see what Ascham is trying to achieve. Book one expounds the virtues and practicality of archery. Book two describes the process of shooting an arrow and hitting the target. It explains how various conditions, shortcomings in technique and equipment affect this. The table shows the steps in this process, connecting them with lines. Like the Nassi-Shneiderman diagrams, conditional branches are implicit in the diagram, but in this case their location is explicitly indicated using the left brace “{“. The right brace “}” indicates a join. The use of the diagram was a deliberate decision by either the author or publisher, as Book 1 has a normal columnar table of contents (pp xiix-xix) like any modern volume, and does repeat a number of lines of text, so there’s apparently no fear of using too many letters. The charting conventions must have been understood, as there’s no instructions for use, although possibly not understood widely enough as the 1571 edition is missing the branching lines from the second decision “how do shooting straight and keeping a length assist hitting the mark?”. Below is a 1788 reprint that used the 1571 edition of Toxophilus with an extra dedication and title page bound in front. It is also possible that this table, too is correct and I’m not following the flow as a sixteenth, seventeenth or eighteenth century reader would as I don’t have a full appreciation of the convention.

Ascham 1571

Here’s another one, this describes the process of bible study and is from the 1615 edition of the Geneva Bible printed in London by Robert Baker. Interestingly, while maintaining the conventions for lines and the left brace used in Ascham, the different processes branching off the first condition are enumerated and the right brace “}” is used to indicate off-page references. This concept is still used in modern flowcharts, just with a different symbol not dissimilar to this “[>“. 

Geneva Bible 1615

Not all examples are so complex, or necessarily used in tables. The first objection in Objections Against the vse of the Bow with the Pike uses a branch, then a join followed by another branch. It’s likely this was written by William Neade, a military technologist and inventor, so the mindset behind the use of a flowchart is closer to the modern application than would at first be apparent. Neade held a patent both for the device to join the bow and pike and for the tooling to mass-produce them, so would fit in the current group of inveterate flowchart (or pseudo-code) users.

Anon 1636

For your edification and viewing pleasure, I’ll finish on George Silver’s Open fight and Of ye short single sword against ye like weapon being both of a length from the page 135 of Brief Instructions Vpon my Paradoxes of Defense. In it, Silver uses the If / Then conditional test explicitly to indicate the decisions and then follows with a process clearly labelled with a numerical sequence.

Silver 1599

References

Anon., Objections to the vse of the Bow with the Pike: And the Answers Thereunto, London, 1636

Nassi, I. and Shneiderman, B., Flowchart Techniques for Structured Programming, SIGPLAN Notices 8, 8 (August, 1973). http://www.cs.umd.edu/hcil/members/bshneiderman/nsd/1973.pdf

Patent Office, The, Patent specification 1949 Act GB69/1634, Neade and Neade’s Patent, Affixing the Bow and Pike Together, London, 1949

Matthey, C. G. R. The Works of George Silver, George Bell & Sons, London, 1898

Waters, J., Toxophilus, The Schole, or Partitions, of Shooting written by Roger Ascham, Wrexham, 1788

Wikipedia – Flowchart, http://en.wikipedia.org/wiki/Flowcharts, accessed 23 April 2010

Wright, W. A., Roger Ascham – English Works, Cambridge University Press 1904

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