Tales from Tanzania: Water, bricks & the ingenuity of Tanzanians

The hard work and ingenuity of the Tanzanians never ceases to amaze me. While traveling one day, we passed the man you see in the photo below, and several more like him. When I asked Simon (my driver guide for the day) what was going on, he explained that they were hauling water.

A water pipeline is provided near every major road and you are welcome to connect to it — but if you do, you get a monthly bill. As most people are unable to afford the connection or the monthly bill, they collect water from the public water point in town and haul it to their homes.

DSCN1399A little while later we passed several structures like this one. Can you guess what it is?

DSCN1217Don’t worry, it took me a minute to figure it out too. It’s a brick furnace.

The locals in this area make bricks out of volcanic rock and clay. When the bricks are dry to the touch, they are stacked into a chimney and baked in place for three or four days in a slow, low fire furnace of their own making. When the bricks change to a dark red color, they are ready for use. They are said to be superior to cinder blocks (another favorite building material here) in every way because they have a bit of flexibility to them and won’t crumble in an earthquake.

Kwa heri!


Watching the River Flow

Water is important. 

That’s a pretty self explanatory statement.  Not only do we need water (at least 8 cups a day), but we are mostly water (60% of us anyway).  It’s one of the indictors we look for in new planets to see if we can use it as future real estate. It’s cornucopia of resources can provide almost everything people need to survive. Animals and plants that grow and live in water can provide food and clothing.  Caves hollowed out by water can provide shelter. The prehistoric oceans provide an area to lay the foundation of hydrocarbons. Water can be drunk to satiate thirst.  The movement of water can power the machines of mankind.

Creative Commons License photo credit: kevin dooley

Man has always known he needs water. Water has always been present whether it comes freely from the skies or washes down in all its fury in a flood.  Agriculture brought about man’s first attempt to channel what water he had.  The landscape was literally remade to get the water to move where it was needed.  Deserts have been made to flower and flowering areas have been made into deserts.  As time went by, we were able to make the movement of water do more for us.  First it was used to help run simple machines, such as mills, where grain was ground into flour.  It was also used in mining, to bring the ore out of the mine, or used to power hammers at a forge.

Water power helped to start the next stage of technological development, the Industrial Revolution. Larger and larger factories were built on rivers to take advantage of the free energy that the flowing water offered them.  Unfortunately they also let the water carry off their excess and trash, making downstream a place to avoid.  While the Thames helped England become a technologic and mercantile titan, it also made the river undrinkable and became so foul that the House of Commons had to be abandoned for a while in the mid 19th century. Water was also the crucial part of steam power that allowed the transportation industry to remake itself from horse drawn carriages to trains and steamboats.

Blast off
Creative Commons License photo credit: fairlightworks

Water is still vital today.

 Most of electricity comes from burning fuels to create steam to move turbines.  Water is also crucially important for solar panels.  Water may sound like an odd thing for solar power to depend upon, but large scale solar thermal arrays can use twice as much water per mega watt hour as a coal fired plant.  Geothermal power plants use water the exact same way as coal fired plants; they heat it into steam and have it turn turbines (although the water could be replaced with other substances). Biomass needs water to grow. 

And of course water is the essential part of hydropower.  Without water (hydro) hydropower would be impossible.  When most people think of hydropower they think of dams (this is where being fond of puns can get you into a lot of trouble, kids. Just leave those dam puns alone).  A dam works by controlling the flow of the water.  It constricts the area the water is trying to move through and uses that movement to turn the turbines.  Because the pathway is constricted, the water backs up and can form a lake (also called a reservoir).  This changes the local environment from a river to a lake. This can affect the local wildlife and lead to erosion downstream.  People (and history) can be affected by dam building as well.  Due to the building of the Aswan Dam in Egypt, over 150,000 people had to be relocated because they were in the flood plain created by the dam.  The Abu Simbel Temple was moved to higher ground as well.

Hydropower can also be generated by the flow of a river, the movement of the waves, and the tides (movement is electricity) and electricity is movement. It is also easy to transfer excess electrical generation into storage by pumping some of the water back upstream or back into the reservoir. 

Electricity generated by hydropower accounted for nearly 7 % of our total U.S. electrical generation in 2010. Over half of the hydroelectricity comes from the 3 states on the West Cost; California, Oregon, and Washington.  While there has been a lot of development over the years, there is still the potential to add more hydroelectric sites and increase the electrical output by a 3rd.  However, the amount of electricity produced by hydroelectric generation varies from year to year with the water cycle.  If you have a year with less precipitation, the rivers may have less water; if the river slows, the amount of electricity is less. Most areas where a large scale hydroelectric plant would work have already been dammed up for use.  The future might be in small scale generators that would help communities near running water.

Creative Commons License photo credit: Perrimoon

All that to say water is, in fact, important. 

We have to have it to live.  We have to have it for our energy production. It takes 10 gallons of water to make 1,000 kilowatt hours using natural gas as a fuel, up to 9,200 gallons for solar thermal and about 20,000 gallons for nuclear. So what happens when we start to run out of it?  I don’t mean that the water on the Earth will suddenly disappear.  It is in a mostly closed system and the water can’t go anywhere (except if water is used on a space ship outside the atmosphere).  What I mean is that on a planet that’s mostly water, only 3% of it is fresh water.  We can’t drink saltwater.  We can’t grow crops with saltwater.  In the coming decades we will have to manage what water we have well. There are ways to generate more fresh water.  Desalinization removes the salt from sea water, but it is energy intensive.  In some areas the excess removal of groundwater can cause subsidence.  This has been an issue in the Houston area. In the 70’s this led to the creation of a Harris Galveston Subsidence District, the only one of its kind in the USA, to monitor and regulate groundwater usage to prevent subsidence. 

Water management will become increasingly important. 

Good water management will make sure that both people and industries get the water they need. Communities all along waterways will have to work together to mange their resource.  Managed from the local level up we’ll be able to sail through any water crisis.

Book List: Water, from snowflakes to African ponds

looking deeper
Creative Commons License photo credit: 416style

There is an excellent article, “The Importance of Water to Human Life and to the Operation of the Human Body” where you learn that next to air, water is the most important element for life to survive.  Water is essential to the functioning of every cell in your body: 2/3 of your body weight is water, including 75% of your brain, 83% of your blood, 22% of your bones, 75% of your muscles, and 90% of your lungs.

Because water is such a broad and important topic, it is difficult to know where to begin.  I decided to approach water from an unusual perspective, so I chose a quote from Wilson A. (“Snowflake”) Bentley whose picture book biography Snowflake Bentley is featured on our book list this month:  “Of all the forms of water, the tiny six-pointed crystals of ice called snow, that form in such quantities within the clouds during storms, are incomparably the most beautiful and varied.”  And Snowflake Bentley should know:  he spent his life photographing snowflakes.

Bentley was born in 1865 in Vermont where he lived his entire life.  According to the award-winning author, Jacqueline Briggs Martin, Vermont, the heart of the “snowbelt” receives 120 inches of snowfall each winter. Although he had little formal education, Bentley had a microscope which he used to study flowers, raindrops, and grass – but most of all, he loved to look at snowflakes—and he never found two that were alike.

When Bentley was 16, he discovered a camera with its own microscope, and convinced his parents to spend their savings on the camera that cost as much as ten milk cows.

Nature's Geometry
Creative Commons License photo credit: ViaMoi

The next winter, Bentley unsuccessfully attempted to photograph snowflakes.  However, a year later he found a way to make it possible for everyone to see “the great beauty in a tiny crystal.”  Winters passed–some winters he could take only a few pictures, and some winters he was able to take hundreds.

Bentley gave speeches about snow and published pictures in magazines.  However, he never became rich because he spent his money on his pictures.  Ironically, after a long walk to photograph snowflakes, Snowflake Bentley died of pneumonia.

The Caldecott Medal is awarded annually by the American Library Association, to the artist of the most distinguished American picture book for children.  Snowflake Bentley won the Caldecott Medal in 1999.

I met author Jane Kurtz when the Museum opened the exhibit Lucy’s Legacy: The Hidden Treasures of Ethiopia.  Jane, the daughter of a missionary, grew up in Ethiopia, and many of her books provide insight into that country.  Jane and her brother Christopher wrote Water Hole Waiting, the simple story of life on the African savanna and the importance of water to life.

Tooth brush
Creative Commons License photo credit: doug88888

When morning arrives, the monkeys are ready to eat and drink.  However, mother monkey grabs her child’s paw to keep him away “from hippo’s yawning jaws,” as the hippos drink and swim in the water hole.  When the hippos leave, the monkey tries again to visit the water hole, but are held back because “the grazers” (including zebras) are running down the path.  But the zebras have to be careful, too; crocodiles are waiting for their breakfast!  Again, mother monkey holds her child back.  And so, the day at the water hole progresses from early morning until evening when the monkeys finally get to drink.

The Authors’ Note provides additional insight into life at a watering hole.  It appears that animals take turns with different species drinking at different times; however, during the dry time, different species may drink together. Children will understand when the Kurtzes explain, “…whether you’re a thirsty monkey hanging back while a lion drinks or a person hiding near a water hole hoping to spot a parade of animals, waiting is never easy.”

The large, colorful illustrations almost give an insight into the animals’ personalities—look at their eyes and expressions!  I am not sure I could last all day watching the water hole, but if the animals resemble the illustrations, I would certainly try.

Because I like the simplicity of the Kurtzes’ book, I also chose another on the same topic: The Water Hole by Graeme Base.  Base is an Australian author whose alliteration-filled alphabet book Animalia and picture book mystery The Eleventh Hour are favorites with teachers, children and parents.  The pages of all three books feature amazing borders to complement the incredible illustrations.

The Water Hole is a counting book that takes you around the world looking at animals and birds in their native habitats, all drinking at water holes.

One hippo is the first to drink at the shrinking water hole located in Africa.  Look beyond the hippo to find the giraffe, the lion, the chimpanzee, the impala, the cheetah, the elephant, the wildebeest, the crested crane and the leopard, all native to Africa, camouflaged in the background.  How do you know which animals to look for?  The border tells you!

Two tigers are visiting their ever-shrinking water hole in India, with ten animals camouflaged in their background.  The book proceeds through three toucans from South America, four snow leopards from the Himalayas, etc., completing the around the world journey with ten kangaroos in Australia, where the water hole has stopped shrinking because it is completely dry.

And, when the water hole dries up all the animals are forced to leave.  Later, it begins to rain.  (Look for a map of the world in the raindrops.)  And, what happens when the water hole fills up?  You know—everyone returns as animals and birds from every continent share one water hole.

Don’t forget:  Water is good for you and it’s cheap!  Drink up!

I can’t find my reading glasses, but I’ll manage.

You’ve probably noticed the magnifying effect of a glass of water or any other clear beverage (the black text to the right of the glass is the same size as the black text behind the glass):

And you probably have some idea that the magnification has to do with the curved shape of the glass and the water it contains: The water in the glass bends light so it appears to us to be coming from an object that is bigger or closer than it really is.

To explore this more, try making differently sized water drops on top of a sheet of waxed paper (the waxed paper helps the water ‘bead up,’ which improves the effect):

You’re aiming for a large drop about 2 centimeters or 1 inch across, and medium and small drops that are, well, smaller.  If you don’t have an eyedropper to help you, you can either pour extremely carefully or dip a pencil or spoon in water and let the water drip off of it.

Look at a page with words through the drops (don’t use your first editions of The Old Man and the Sea or Einstein’s General Theory of Relativity, because the water will eventually seep through the waxed paper and make you very, very sad).  Do you see any differences between the larger and smaller drops?

This looks much clearer if you try it yourself, so go do it! 

You may be thinking “My large drops (possibly puddles) don’t seem to change anything; why do the small drops work so much better?”  To explain this, try looking at your drops from the side (your eyes should be level with the surface of your table:

The shapes are different: The largest drop looks almost flat across the top, while the smallest drop makes a very tidy little dome shape.  Another way to say this is that the smallest drop’s surface is more sharply curved, or is more convex than the larger drops (convex surfaces bulge out, concave surfaces “cave in.” And it turns out that the less convex the surface of the drop, the less it magnifies.  If you want a more in depth explanation with diagrams, check out this site.

Convex and concave lenses are used in all kinds of cool equipment. For more information on lenses and the anatomy of your eyeballs, check out The Anatomy of the Eye.