I do hope that this is a reasonable extension of the proper subject
matter of Qalam.

One item of interest is signed-ternary* notation, although probably
of more interest to mathematicians than those primarily interested
in writing text, names, etc. Considering this, I'll be concise.
It's positional -- The columns are power of three:
... 243 81 27 9 3 1 (and higher, as required (Think R to L!))
*radix-3; decimal is radix-10, the system we all know.

Numbers consist of groups of three numerals: [+] and [-] signs, and
zero. Furthermore, it is not at all necessary to separately define
such a number as positive or negative. The idea of a negative
digit might seem odd, but it's legitimate.

Simple equivalencies, with signed ternary
given first, in [square brackets]:

[+] = 1, [+ 0] = 3, [+ 0 0] = 9
[-] = -1, [- 0] = -3, [- 0 0] = -9

Negative digits permit all integers to be represented:
[+ -] = 2 (This is 3 - 1)
[+ 0 -] = 8 (This is 9 - 1)

A -2 would be written [- +], and a -8 would be [- 0 +].

This notation was proposed for practical use (with conversion
tables, or methods) in an historic mechanical calculator invented
ca. 1840 (iirc) by Thomas Fowler, in England, that needed little if
any critical machining. The calculator mechanism, itself, was, for
the most part, extremely simple and unsophisticated. Unfortunately,
many significant details were either not documented or lost.

<http://www.mortati.com/glusker/> shows the reconstructed machine.
If you Google on [ thomas fowler calculator ], you should find more
that 1,300 hits.

I can answer some questions about the topic, because I helped Mark
Glusker a bit with the design of the reconstruction. To [say] more
seems inappropriate.

=== Different topic: Use of Zero by the Chinese ===

Chinese numbers (I not sure of Hangzhou(?) numerals) do not use
zeros. However, in the 18th century, iirc, a Chinese trig. table
simply could not be printed without zeros, so they used (surprise!)
a simple circle for the zero.

My source is a book about the history of numbers/numerals:
_Menninger, Karl A., Number Words and Number Symbols, ...tr. by
Paul Broneer from the rev. German Ed._ MIT Press, 1969. I do not
recall the page nor chapter, but there is an illustration. Btw,
there is another, better-known Karl Menninger; this is not [he].

Btw, Googling on [history numbers book] seems fruitless; I was
probably at the 100th hit and still hadn't found this. The book is
in our local library's (Minuteman) catalog.

This book did have some commentary about the use of letters as
numerals, but I no longer recall how much. Some vandal had removed
all the pages dealing with Jewish numbers in our local library's
copy; of course, I don't know why.

(I don't expect to comment much further on writing numbers, except
to say that browsing the Unicode glyph charts and seeing the
traditional numerals was a real treat. It would be fun to prepare a
chart showing all of them.)

Best regards,

- nb // Waltham, Mass.