Category Field Guide to Appropriate Technology


Silk is a fiber produced by the silkworm to make a cocoon. The fiber is unwound from the cocoon. Creating silk thread involves cultivating the worms, collecting the cocoons, unwinding the cocoons, and reeling several filaments together. Each of these processes can be done by hand, although most are mechanized.


Silkworms eat only mulberry leaves. The entire process can be controlled by keeping the worms in a controlled environment; protecting them from ants, mice, and disease; and feeding them mulberry leaves. The silk that is produced is called “real silk.” Wild silkworms will eat other kinds of leaves, as well as mulberry, and fend for themselves. The silk from wild silkworms is thicker and less lustrous, and is called “tussah” silk.

Cultivation starts with eggs...

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Making rope by hand is time consuming. If you plan on making larger quantities of rope, it may be preferable to build the simple machine shown in Figure 22. The machine is made of two devices, the twisting end and the laying end. Making a Y tool, or spreader, out of hard wood is also advisable. The twisting end always remains stationary, and the laying end must be able to move closer to the twisting end, since the rope gets shorter after twisting. After the two ends of the rope machine are correctly positioned, tie one end of the twine to the laying end hook. Then hook the twine over a hook on the twisting end and then back again over the laying end. Repeat this back and forth process until each of the hooks on the twisting end have two lengths of twine on them...

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The tribal and rural people shared elements of local knowledge systems pertinent to the use of water and soil. This indigenous technical knowledge included information on botanical indicators of shallow ground water, such as the tree Ficus glomerata, known locally as umbar, and the associated bottomland flora. This information tended to be supported by accounts of ancient, Indian hydrology, such as the Brahat Samhita, written by Varaha Mihira in the sixth century (see Tagare 1992) and by modem field observations. In addition, the people provided useful information on the relationship between terrain features and groundwater discharge, local strat­egies of land use, and a local classification of soils.

Indigenous technical knowledge was combined with project research on hydrology and hydro...

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Two pour-flush toilets are shown in Figure 22. One or two liters of water are poured in by hand to flush the excreta into the pit. (The “soakaway” shown in the figure is discussed below.) Note the water seals in both models, which prevents odor development and mosquito breeding. An advantage of the offset pit design is that the toilet can be inside the house and the pit outside. If two pits are built, they are used alternately. When the first pit is nearly full, the second is connected to the toilet. During the period the second pit is being used, a year or so, the waste in the first pit decomposes into a humus suitable for fertilization. Such a system can be easily upgraded by attaching to a sewer line...

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Edited by ROBERT ELLIOTT Independent Builder


Robert Elliott

According to Webster’s the word tool is derived from the Old Norse tol, meaning “to do or to make.” While we usually think of tools as objects, we would do well to keep the derivation in mind. For me, tools are extensions, enhancements, or amplifications of my body. I can pound with my fist but pound better with a rock—and better still with a hammer. I can see an amazing world using only my unaided eyes, but with tools, this world is expanded a million times beyond my natural limits.

An average person, such as myself, comes with a pretty good set of tools—a part of that wonder of evolution, the ultimate toolbox, the human body...

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Based on How to Make a Folding Machine for Sheet Metal Work, Rob Hitching, Intermediate Technology Publications, London, 1999

A machine that folds metal and can be made in a village workshop is shown in Figure 23. This machine can increase the range of products that a village metal worker can produce. The machine can be made in a small-scale shop by the person who will use it. Machines like this can improve greatly the capability of small shops.



Sheet metal folding machine.


The machine can bend sheet metal to produce the shapes shown in Figure 24. It will bend metal of 16 gauge or less, corresponding to 1.5 mm thick, and 1 meter wide.

The machine can be built in a small workshop using locally obtained materials...

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When a female duck tries to hide or sits on a nest more often, she is probably ready to set. Make her a setting nest in a quiet, dark place well sheltered from rain, sun, and wind. The nest can be a simple hole in the ground or a box lined with clean, dry grass or straw. A female duck can cover 10 to 12 eggs, so try to collect this many eggs from your flock. However, when you collect the eggs, handle them very carefully. If you shake eggs too much, they may not hatch. Eggs that are very small or very large may not hatch—choose medium-sized eggs. Eggs to be used for setting should be no more than ten days old. The eggs should be clean. If they are dirty, clean them with a soft, damp cloth...

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Based on Better Farming Series 12. Raising Sheep and Goats,

A. J. Henderson: Food and Agriculture Organization of the United Nations, Rome, 1977,

ISBN 92-5-100152-9


The traditional way of breeding sheep and goats does not take much work, but it also does not produce much. It takes little work because the animals are not looked after. They are not fed, they are not given water to drink, and they are not given any shelter. This method of breeding, however, produces little. The animals are small, they are often ill, and their young ones often die. If a farmer breeds sheep and goats in the modern way, he or she can earn more money.

A few terms should be defined: A flock of sheep consists of 1 male, called the ram; 20 females, called ewes; and young ones call...

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