During the second half of the 19th century a large number of Jewish popularizers in Eastern Europe took upon themselves the task of spreading knowledge of the natural sciences amongst the learned Hebrew speaking Jewish intelligentsia of Eastern Europe. This was part and parcel of the processes of enlightenment and acculturation of Jewish society and an important chapter in the revival of Hebrew culture. This group of popularizers continued this tradition of writing about scientific developments for many years and eventually their books and articles reached ever larger circles of readers eager to acquire new scientific knowledge.

Many of their publications aimed to deal with the wonders of the universe and many of them described new technological inventions. Other publications tried to explain to the ever expanding circles of readers changes that have taken place during the second half of the 19th century in the fields of physics, astrophysics, chemistry, biology, physiology and more. Their publications explained to the Jewish intelligentsia such processes and terms as energy and its use, electro-magnetism, thermo-dynamics, chemical substances and much more. Often they had to invent a terminology that had not previously existed in the Hebrew lexicon.

At the same time this new scientific knowledge revealed the principles and laws governing the world around them. Many of these popularizers were observant Jews and the book deals with the way they struggled with the challenge of reconciling their religious beliefs with scientific discoveries, a challenge that persisted into the twentieth century. The book describes these developments which led to the creation of the field of science in Hebrew - it is a collective biography of the ever-larger group of popularizers who opened a new field of knowledge and the manner in which they tried to explicate it to an ever-larger public