JF Ptak Science Books Post 2065

There is something enormously appealing in the general nature of old numbers, numbers written or printed long ago, numbers making an appearance in the general sense of ordinary and commonplace, everyday garden variety numbers (like the example above and it continuation below), as well as in more famous numbers, numbers that present a concept for the first time, or offer a proof in thought and conjecture (as seen further below with Mr. Stevin).

The first example is from a worn copy of a common early-ish 19th century American math textbook by Rosell C. Smith, *Practical and Mental Arithmetic, on a New Plan, in which Mental Arithmetic is Combined with the Use of the Slate*... which was printed in Hartford beginning in 1829 (my copy being printed in 8136). It was a popular book, and it claimed to make math more useful by using calculations for problems to be figured in terns of dollars and cents, thus giving the exercises the chance of direct application to the daily grind. My copy of this book is very worn--not the worn that comes from mistreatment, but rather use-worn, the book being smooth and lustrous from repeated and deep use, handled so much over the years that the paper covers have a very definite and smooth patina.

In any event Mr. Smith's numbers have a special bit to them, something nor-quite-like-everything-else. The care and the design and placement of the numbers is very attractive, even if it makes the numbers sometimes a little illegible.

The numbers have a certain beauty to them, as does the space aloted for their answers:Famous numbers have a distinct beauty as well, in the more refined and exalted antithesis as those numbers for a simple sum problem: from two ends of the spectrum ,sometimes, though they both meed in the middle where the numerological beauty occurs. A great example f famous numbers might belong with Simon Stevin (1548-1620), who introduced the idea of decimal numbers in his 36-page *De Thiende* ('The Art of Tenths")
in 1585 His was an idea that replaced much more cumbersome earlier methods of
representation. So, the number 3.14159 would be written in the Stevin
notation as (where in this case numbers enclosed by brackets, i.e. "[9]"
would have been represented in print as a 9 within a circle)
3[0]1[1]4[2]1[3]5[4]9[5]. It is also seen here:

One item that attracted my attention--easily so--was the following problem:

It was also the only illustration in the 284-page book. And it makes sense, I think, because squirrel hunting is just what people did at this time, and the calculation could be a useful one. Still, it is an unusual image to set to work illustrating a math problem--and interesting.

## Comments