Counting to find out

This lesson asks you to read data sets by asking questions and drawing conclusions. The museum offers one count recorded in history, whose figures rest on a single source and which the record says needs an additional source; collecting data, frequency tables, graphs and decisions are the class's own work. ¹

Look at the two numbers of looms. Which is more? Write one question the numbers can answer and one they cannot. Who might need other information?

The "Fragments of Gold" records for 837 AH a count of the weavers in Alexandria and of the villages of Egypt, and compares it with what had been before ². In Alexandria there were eight hundred looms, while at the end of the eighth century there had been fourteen thousand. The army registry counted the villages of Egypt as two thousand one hundred and seventy, where at the beginning of the Fatimid state there had been ten thousand ². The record says the figures are given on the source's own authority and an additional source is needed. It does not say who ordered the count or why.

All these numbers come from one book. Why would you trust a number more if a second book gave the same count, and what would you do if the second book gave a different one?

• The Loom and Village Census of 837: the figures as the record gives them, with the note that a second source is needed.
• Al-Mu'tadid billah II: an Abbasid caliph in Cairo between 815 and 845 AH, in whose reign the museum places this count.

Read the record on the census of 837 AH. Write one question the numbers can answer and one they cannot, and say what other source you would want to check them against.