Story 05: Memoirs of a Bubble BlowerStory | Related Media | Archives | Print | eMail | Search
Written by Bernie Zubrowski
During this time I began to see the value of letting children construct and play around with working models of historical technological artifacts—water wheels, windmills, houses, bridges, pumps, and tools. There is a big difference between a working model and a replica. Lots of craft books, as well as some children's science/technology trade books, featured step-by-step instructions that showed you how to make a model of a water wheel or a house. The main point of the activity was to make something like these artifacts. But once constructed, there wasn't much you could do with these "models." You couldn't experiment to find out how a windmill worked or test a house to see where it was strong or weak. Because of my previous work in the Elementary Science Study and the African Primary Science Program, where kids actually explored scientific phenomena in simple but direct, hands-on ways, I felt that these models should be taken a step further. Another part of the impetus to do so came from a book I came across at that time called Working Models of Historic Machines by Aubrey F. Burstall. It showed a series of plans for making devices such as bow drills, lathes, and water pumps. These weren't just attractive models, but actual working models similar to the real things as they existed hundreds or thousands of years ago. There were no specific step-by-step instructions on how to build them but the plans were clear enough that it was possible to construct something close to a device that functioned like the real thing.
Having run a toolmaking program while working in Kenya for the African Primary Science Program, I thought it would be of interest to elementary school age children to make primitive tools and to work with primitive "machine tools" such as a lathe. Drawing upon the African experience and some models from Burstall's book, I designed a series of activities that followed the development of cutting and shaping tools over a period of several thousand years, starting with Stone Age implements and progressing to tools used as recently as 150 years ago. The overall concept was to have students experience the different ways in which people in the past made tools and how they used these tools to shape materials such as wood. My approach to science learning was becoming consistent: first, get kids to play around with real stuff. And that approach was already one of the hallmarks of The Children's Museum in all subject areas.
The toolmaking program became one of the programs offered for elementary school extended field trips. In the first session, students worked with stone tools trying to shape pieces of wood or cut scraps of leather. In the next two sessions, they became blacksmiths working with charcoal fires and shaping nails into drill bits. Somehow we managed to do these activities with only a few burns and scrapes. After forging these tools, they used the shaped nails they had made as drill bits to construct two kinds of primitive tools—the bow drill and pump drill. Eventually, the kids took their handmade tools back to their school classrooms. The sharp nails they had fashioned were inserted into sixteen-inch-long dowels that were used as cutting tools with two kinds of primitive lathes we had set up—a bow lathe and a pole lathe. The lathes were used to shape pieces of dowels into a curved surfaces which could later be cut and made into wood beads.
Working with very hot materials and primitive tools supplied real excitement to these projects. The students hammered away at hot nails held with pliers. They showed pride in honing the ends of the nails into sharp points. Even though they did not complete shaping a piece of wood in the two kinds of lathes, they still were quite excited to have the opportunity to use these real devices.
Over several years, similar programs were developed for other older technologies. Water-lifting devices and pumps took students through a series of activities where they constructed and operated very old water-lifting devices such as a shaduf and a noria—a reverse water wheel. They also explored devices such as the rag and chain water-lifting device and then moved on to a simple suction pump. They spent several sessions exploring how siphons work. The culminating activity was a demonstration of how water can be lifted using heat to create a partial vacuum in a jar. This was a simplified and primitive device representing the beginning of the steam engine. The earliest steam device was used to pump water out of mines. Thus, students were taken through a series of activities where they experienced several ways of dealing with the problem of moving water through a vertical distance. Through these activities, they experienced a history of engineering where different devices had been invented to solve this problem.
Other programs, devoted to exploring the historical development of technical devices by allowing students to construct and operate working models using simple materials, included the following titles:
- Wheels at Work (pulleys, water wheels, water turbines, and water wheel clock)
- Timekeeping (water clocks and exploring the functioning of mechanical clocks)
- Extractions and Other Chemical Processes (making perfumes and exploring fermentation)
- Dyes and Pigments (grinding rocks to make pigments)
- Wind Machines (making and testing models of sailboats and windmills).
Other topics I thought might be interesting to develop (before I ran out of funding) were: shelters, containers, weapons (yes, weapons in a children's museum!), weaving and weaving machines, musical instruments, clothing, and fire and light.