Dec 9 - Islamic Mathematicians

“He also sponsored a geodetic survey to determine the length of a degree of a meridian in order to find the circumference of the earth. (That the earth was a sphere had been known to the educated since the time of Plato, early in the fourth century B.C.E.)” (3-4)

I had always thought that the realization of the Earth's roundness occurred later in human history. I think it would be a fun, practical geometry lesson to have students determine the circumference of the earth, although I'm not sure which grade in would be most appropriate to. 

Also clearly the current subset of Western society that believes the Earth is flat needs a lesson in ancient geometry. 

“The breadth of al-Bīrūnī’s studies, if not already sufficiently demonstrated, is plain from his work Pharmacology, which he wrote in his eightieth year while his eyesight and hearing were failing. The bulk of the work is an alphabetical listing of about 720 drugs telling, in addition to the source and therapeutic value of each, common names for the drug in Arabic, Greek, Syriac, Persian, one of the Indian languages, and sometimes in other languages as well.” (12)

This one is not math related, but the its astounding that this many drugs had been found, catalogued and named in so many languages. I wonder about the definition of "drug" used at this time, and how many of these are still considered such. 

“The other is his suggestion that the idea of number needed to be enlarged to include a new kind of number, namely ratios of magnitudes. For example, in ‛Umar’s view, the ratio of the diagonal of a square to the side Ö2, or the ratio of the circumference of a circle to its diameter (π), should be considered as new kinds of numbers. This important idea in mathematics amounted to the introduction of positive real numbers” (16)

This is noteworthy due to being the origin of the set of positive, real numbers. This would be a useful inclusion in a lesson which introduces the subsets of the real numbers, alongside the histories of the other sets. I also think using π, and maybe Ö2, to introduce proportionality  could be very useful. In my short practicum I gave a lesson on scale factor, which involved introducing proportions, and I think π would've been a much more natural way to do it.