Superconductors have been known about since the turn ofthe century. Recently there has been a renewed interest with the discovery of the new, high-Tc materials since 1986 1]. These compounds become superconducting at much warmer temperatures than any pre viously known. In fact, many of tthem superconduct at temperatures above the boiling point of liquid nitrogen, making the observation of the transition both accessible and inexpensive. It was obvious immediately that these materials could have a tremendous technological impact, or lead to further materials with even higher transitions. For this reason there has been an intense effort by scientists in both academia and industry to study these materials. The scientificand industrial communitieshope to learn what makes these materials work. For, learning how these materials work not only increases mankind's overall knowledge of his world, but could make some person or company quite successful if the information were used and developed correctly."

This is a new release of the original 1942 edition.

This is a new release of the original 1942 edition.

A pioneer in the birth control movement both in the United States and abroad, Dr. Clarence J. Gamble began his work as a volunteer in Philadelphia in 1929. Because he was convinced that the health and happiness of women and children and, in fact, entire families depended on adequate spacing of their babies, he helped to establish family planning clinics in a dozen American cities before he was forty years old. Dr. Gamble's major concern was to provide a safe, reliable, and cheap contraceptive that poor women who had no access to running water or modern conveniences could use. After World War II and the population explosion that followed it, Dr. Gamble expanded his efforts in what he called the Great Cause to help those in the developing nations who wanted their people to be able to choose when to have children and how many to have. Every Child a Wanted Child is more than the biography of a unique man. It is a record of the ups and downs of the birth control movement in the United States and in Italy, Japan, India, and parts of Asia and Africa.