Chapter one is a quick review of the nature of light, with interesting historical information and a quick blurb on spectroscopy and an interesting table showing the types of atomic/nuclear transitions and the emission wavelength associated with each. This chapter is really just an extension of the preface.

Chapter two introduces the basic concepts of polarization in an electro-magnetic wave, including the equation of the electric field for elliptically polarized light, with extra emphasis on the two extremes (linear and circular polarization). Chapter two includes some useful pictorial examples of polarized light. The authors have been careful to define their terms well. They also have a rather lengthy footnote in chapter two that establishes their conventions for describing circularly polarized light. Also helpful is their inclusion of a list at the end of each chapter containing the mathematical symbols used in the chapter and their meanings.

Chapter three introduces common devices used to control polarized light, including linear polarizers made of dichroic as well as birefringent materials, and those constructed by such techniques as stacks of tilted glass plates. The chapter also introduces the concept of phase plates used to construct retarders, and gives useful physical information for materials commonly used in their construction. Artifacts due to retarders and polarizers are also discussed, along with a rather superficial discussion about depolarizers. The end of the chapter has a neat discussion about Haidinger's brushes and how you can use them to "cure" polarization blindness.

Chapter 4 is among the book's most useful. This chapter introduces the Jones Calculus, Mueller Calculus, and the Poincare sphere. This is the chapter in the book that I find myself returning to most often, along with appendix A (Jones and Stokes vectors of various forms of polarized light), and appendix B (Jones and Mueller matrices for various polarizing or polarization-sensitive optical components). Chapter 4 and appendixes A and B alone are sufficient justification for purchasing the book. The appendices, for example, are quite complete, listing matrices for everything from the general elliptical polarizer to the general elliptical retarder (there are 19 entries for Jones matrices alone).

The authors develop the Jones and Muller calculus in a manner that's easy to follow yet both rigorous and insightful. The book makes no apologies about the use of mathematics, and uses equations and derivations liberally. The level of mathematics is easy, however, being nothing more than linear algebra for the most part. There are also useful examples of how to use the Jones and Muller matrix methods to solve simple problems. The chapter introduces the Jones calculus first, then the Muller calculus, and finishes off with a good discussion and explanation of the Poincare sphere.

Chapter 5 covers the Jones and Muller calculus again, this time with more mathematical involvement and in greater detail. Chapter 5 also describes the Poincare sphere in more detail as well. Chapter 4 aims more at the initial introduction and relatively simple practical applications, while chapter 5 deals with such subjects as the analytical relationship between the coordinates of the Poincare sphere, the Stokes parameters, and the electric vector describing the light.

The first 5 chapters constitute the book's coverage of the general principles of polarization. The rest of the book deals with applied issues relating to polarization. For example, chapter 6 deals with the physics of spectroscopy and polarized light, chapter 7 deals with orientation and photoselection effects, and chapter 8 (the last chapter) covers polarized light in condensed phases.

I bought the book because I wanted a complete and authoritative reference for the general principles of polarization. I was especially looking for a text that succinctly yet accurately and completely introduced the mathematical concepts of the Jones and Muller calculus, and that provided a clear description of the Poincare sphere. Furthermore, I wanted a reference book that listed the transfer matrices (both in the Jones and Muller calculus) for a wide assortment of idealized and real-world optical components that interact with polarized light. The book has been everything I was looking for and is the best I've found on the subject.

If you work with or have an interest in polarized light and it's quantitative analysis, I highly recommend this book.

A real life conspiracy that reads better than any fiction.

A brilliant young officer, falsely accussed of treason. A trial with secret documents that have been forged. A true traitor on the loose. And the direct involvement of at lease two governments. A fantastic display of courage when it was least expected. An officer that survives Devil's Island on nothing but courage and a desire to clear his name.

Add a coverup to protect the original court, and a government that aids the conspirators, and it is complete. A fantastic entry into the 20th century.

In THE SHAMANS OF PREHISTORY, Jean Clottes and David Lewis-Williams put forth their interpretation of the meaning of Paleolithic cave art. Clottes is currently investigating Chauvet and Lewis Williams is a professor of cognitive archeology affiliated with the University of Whitwatersrand in South Africa.

During the last Ice Age, Paleolithic humans gathered in the warmer parts of the European continent in what is today southern France and northern Portugal and Spain, along with large numbers of animals including horses, bison, deer, aurochs, and others. For some reason, these humans felt compelled to depict some of these animals in "parietal" or cave art. The discovery of this art has launched much speculation.

Early on, experts suggested that the cave art was "art for art's sake" (posited by anti-church scientists who could not accept any religious connection). Most recently, experts in Structuralism have suggested binary patterns underlie the meaning of the art, but these patterns are so general as to be unhelpful.

The most persistent interpretation of the art during the past 100 years has been that it was created in conjunction with sympathetic magic rituals used to increase the size of herds of animals hunters stalked. But this interpretation has many flaws. For one thing, the area surrounding the caves was brimming with game at the time the art was created. For another, many of the animals consumed by Paleolithic humans were not depicted (fish, birds, boars, for example). For another, horses outnumber other beasts pictured, and although they were sometimes consumed by humans, the bones left behind in various camp sites indicate horses were not at the top of the menu. Other problems with the "hunter" interpretation lie in the actual depiction of the animals-spears and arrows are often placed at odd angles for killing; animals are placed at odd angles for living or dying; animals appear to be more alive than dead; pregnant females are seldom shown--and last but not least, some of the animals are predators themselves. Naturalists that they were, Paleolithic folks certainly understood the source of baby animals and they certainly would not have wished to increase the numbers of their competitors.

Clottes and Lewis-Williams propose another interpretation of the cave art -- Shamanism. The term Shaman is taken from the Siberian word Tungus-the name of one who goes into a trance and has visions. All humans are capable of entering a trance or "altered state" and cultures around the world exhibit variations of Shamanism -- including many orthodox Western religions. Some enter a trance via drugs (wine, peyote, etc.), others engage in ritual behavior (chants, songs, and/or dancing). Shamanic trances produce out-of-body experiences involving various apparitions which may or may not be rendered into art forms.

I found the authors arguments concerning Shamanism persuasive and logical. The evidence they offer to support their thesis is excellent (many colorful photos). Their interpretation is helpful while not overreaching. Probably the most important aspect they stress is that while there is much diversity in cave art, a pattern is present. Best of all from my perspective, this thesis is gender and age neutral. Whatever Paleolithic humans did, women probably took part. This is a beautiful Abrams art book.

In Hoc, Morton

Especially useful for programmers.