Dr Palmer examines the chronological stages to the development of the concept of valency up to 1930.

Valency patterns and valency orientation have been frequent topics of research under different perspectives, often poorly connected. Diachronic studies on these topics is even less systematic than synchronic ones. The papers in this book bring together two strands of research on valency, i.e. the description of valency patterns as worked out in the Leipzig Valency Classes Project (ValPaL), and the assessment of a language's basic valency and its possible orientation. Notably, the ValPaL does not provide diachronic information concerning the valency patterns investigated: one of the aims of the book is to supplement the available data with data from historical stages of languages, in order to make it profitably exploitable for diachronic research. In addition, new research on the diachrony of basic valency and valency alternations can deepen our understanding of mechanisms of language change and of the propensity of languages or language families to exploit different constructional patterns related to transitivity.

Orbital Symmetry: A Problem-Solving Approach was born of the necessity to present to students Woodward and Hoffmann's approach to pericyclic reactions. Hence the tone is introductory, and the book is addressed primarily to an audience of advanced undergraduate and beginning graduate students. The text seeks to familiarize the readers with several of the more often encountered methods of analyzing pericyclic reactions, and these methods should enable the analysis of virtually all of them. Problem solving is the foundation of the approach. Both the introductory and theory sections include problems to prepare the reader for the more extensive chapters of problems that follow. All problems (except those in Chapter VII) are answered in the text and are fully referenced where appropriate. Many of the problems require the use of molecular models if they are to be appreciated. Prentice-Hall's ""Framework Molecular Models"" and Benjamin's ""Maruzen Models"" are best suited for the construction of the highly strained molecules often encountered in the problems, and their use is recommended.

This classic exposition explores the origins of chemistry, alchemy, early medical chemistry, nature of atmosphere, theory of valency, laws and structure of atomic theory, and much more.