Crystals

The book offers a clear, nontechnical account of crystallography, tracing observational and theoretical advances and illustrating experimental phenomena in polarised light. It explains symmetry and crystal habit, rules limiting possible faces, zones and face construction, and the lattice concept with unit cells and the enumeration of crystal point-systems. Historical contributions such as early structural ideas, isomorphism and morphotropy, polymorphism, and enantiomorphism with related optical activity are discussed, along with liquid crystals and practical experiments on growth from solution. The chemical implications, including the Pope–Barlow view linking crystalline arrangement with valency, are presented cautiously and without heavy mathematics.