Science and Technology Words from the More Recent Past to the Present, Part 2
(terms appearing in some "scientific" areas from about 1800 A.D. to 1899 A.D.)
A very old method of treatment that originated in China.
synthetic fertilizers, pesticides, and herbicides (weed-killers) are examples of such chemicals.
In ancient times, the name used for a gas.
2. The mixture of gases that make up the earth's atmosphere.The principal gases that compose dry air are: Nitrogen, 78.09%; Oxygen, 20.95%; Argon, 0.93%; and Carbon Dioxide, 0.033%.
Another important constituent of air is water vapor which varies from 0% to about 4%.
In the United States, the standard is 120 reversals or 60 cycles per second. Electricity transmission networks use alternating current because voltage can be controlled with relative ease.
Alternating current is easier to transmit over long distances than direct current (DC), and it is the form of electricity used today in most homes and businesses.
2. The study of humans, concentrating on culture, defined as non-genetic human behavior.
- Cultural anthropology, contemporary cultures.
- Archeology, cultures of the past.
- Linguistic anthropology, languages and their cultural roles.
- Physical anthropology, the evolution of humans and the relationsip between biology and culture.
Index of additional Scientific and Technological Topics.