Introduction
Prior to begining this
project you should have read and understand the Caveman
page on dyes.
We will be working with two dyes - sumac and walnut.
Each student will dye a 1-meter strand of wool. In addition, you will have
to code your wool using the binary number system to identify your piece.
Sumac
You will recall from our measurement project
that cotton is cellulose and is easily dyed with sumac which has a natural
tannic acic mordant in its juice. Wool, however, is made of protein which
did not take the sumac dye. In this laab we will add an iron compound as
a mordant. See if we get a bright color or dark color. Do you think heating
the dye in an iron pot would have the same effect?
Walnut
In the measurement lab, walnut
did not dye with sumac. In this lab we will use alum as a mordant (contains
aluminum). What color does the wool turn. Would a different mordant, copper
for example, give the walnut dyed wool a different color?
Identifying Your Yarn
After you have made a length
of yarn, how can you tell yours from all the others in the class? Since
each student in the class can be assigned a number (1-28) in alphabetic
order, one good way is a number code. Using the "binary" number system,
numbers can be made by a series of knots tied in the end of the yarn.
Our traditional decimal number system
is a "base ten" system, where each digit can be 0-9. The binary system
is "base two", where each digit can be 0-1. To represent a number as high
as 28 we will need a 5-place number in binary. Each of the five places
will be a "0" or a "1". Zero's represent zero and 1's represent the
place value which is:
Place 1 has a value of 1
Place 2 has a value of 2
Place 3 has a value of 4
Place 4 has a value of 8
Place 5 has a value of 16
(each place has a value two times
the previous place)
Now make a 5-place number of 0's and
1's, add the 1's place values, and you will have the decimal equivalent
number. Remember, read binary right to left.
For Example
00101 = 5
01000 = 8
00011 = 3
11100 = 24
10110 = 22
Put a knot in the end of your yarn. This is a "starter" knot and is not part of your number. Now work to your left putting a knot or no knot each centimeter (for 5 centimeters).
Could you take this concept and make a language out of it? The ancient Incas of Peru did just that, long before computers. They called it the Quipa knot language.
The ASCII, a standard for computer text is a sample
of the English language expressed in binary form. Can you spell using the
ASCII equivalent of the alphabet?
Criteria - you MUST pass both quiz and project.
Quiz
Return to Physical Science Main Page
Return to Measurement Page