The Recombinant-DNA Debate
The four-year-old controversy over the potential biohazards presented by the gene-splicing method and the effectiveness of plans for their containment is viewed in a broader context
Features
The Atmosphere of Mars
It is less than a hundredth as dense as that of the earth, but it is still the principal agency altering the surface of the planet. Its winds and clouds resemble their terrestrial counterparts...
Viral Hepatitis
Much has been learned in recent years about the epidemiology and immunology of this debilitating disease. Soon a vaccine should be available that will offer protection against one form, hepatitis B...
Biological Regeneration and Pattern Formation
Certain animals can grow new legs and even extra ones. Studies of how they do so are revealing much about the basic principles of the organization and growth of complex structures in animals...
The Solidification of Cement
What happens after water is added to cement to transform it from a soft slurry to a rock-hard mass? Chemical reactions give rise to a system of interlocking particles that knit the material together...
Anions of the Alkali Metals
Alkali metals, such as sodium, are familiar as cations: positively charged ions formed when atoms lose an electron. Now it has been learned they can also gain an electron to form very reactive anions...
The Compound Eye of Insects
It has hundreds of facets, each representing an ommatidium, or "little eye." The size, pattern and aiming of the ommatidia are determined by the requirements of the insect's way of life
Gauss
A child prodigy who became the leading mathematician of his age, he was equally at home with the abstractions of number theory, the long calculations of astronomy and the practicalities of applied physics...
Departments
50 and 100 Years Ago, July 1977
Science and the Citizen, July 1977
- Letters
Letters to the Editors, July 1977
- Recommended
Books, July 1977
- Mathematical Recreation
Mathematical Games, July 1977
- Amateur Scientist
The Amateur Scientist, July 1977
- Departments
The Authors, July 1977
Bibliography, July 1977
