In 1925, the study of colloids was one of the most popular topics in American science. Researchers from such diverse fields as biology, physics, medicine and chemistry were looking at colloids and finding them in everything from cell physiology to chemical warfare gases. There were major conferences on colloids and plans to build a national colloid research centre. Throughout the first half of the decade, no less than 25 per cent of all chemistry papers published in North America were on colloid research. Ten years later, colloids had virtually disappeared as a research classification. The US National Research Council dropped the category of colloid research from its annual review of American chemistry, and even those researchers who continued to study colloids renamed themselves, often as surface chemists or phase state chemists. The leading advocate of colloid science in America, Wilder Bancroft, lost control of the Journal of Physical Chemistry, the leading publisher of colloid research, and was severely ridiculed by the medical community over his claims to have discovered a colloid basis for many diseases, including alcoholism, hay fever and mental illness. Offering a comprehensive account of the early history of colloid chemistry, Dr Ede also looks at the complex issues that led to the rise and sudden decline of the status of colloid research, to a point where the term 'colloid science' became one to be avoided by young scientists who wished to be considered serious researchers. The book prompts interesting questions about why the prestige of different branches of science rises and falls, the practice of scientific research in early twentieth-century America, and the future of chemistry as a scientific field.