Colloids

1.2 A HISTORICAL PERSPECTIVE

While the fields of interface science and colloid science are now know to be intimately related, such was not always the case. In the history of their development, thetwo branches evolved from somewhat different sources and slowly grew together as it became obvious that basic laws controlling phenomena related to the two were, in fact, the same.
Although theformal studies of interface and colloid science began in the early nineteenth century, humans observed and made use of such phenomena thousands of years earlier. The bible and other early religiouswritings refer to strange clouds and fogs, that were colloidal in nature (aerosols). Ancient Egyptian hieroglyphic paintings show scenes of slaves lubricating great stones being moved to build pyramids andother monuments. Hebrew slaves made bricks of clay, a classic colloid, while many ancient seafaring cultures recognized the beneficial effect of spreading oil on storm-tossed waters in order to helpprotect their fragile crafts. The preparation of inks and pigments, baked, bread, butter, cheese, glues, and other substances all represent interfacial and colloidal phenomena of great practicalimportance to ancient cultures.
In more modern times, such notables as Benjamin Franklin began to take formal notice of interfacial and colloidal phenomena in philosophical discussions of, for example,the amount of oil required to cover a small pond in London completely with the thinnest possible layer (monolayer coverage). The first important quantitative analyses of surface phenomena were probablythe works of Young, Laplace, Gauss, and Poisson to be discussed later.
From the middle of the nineteenth century on, understanding of the phenomenology of interfaces became better at the molecularlevel, although the nature of the forces involved remained uncertain the advent of quantum mechanical theory in the 1930s. the study of colloidal phenomena followed a similar track in that certain...