[...]... available, attempting to find uses for them, in addition to providing illumination Some of the viscous materials were investigated as substitutes for the vegetable and animal oils previously used for lubrication, mainly those derived from olives, rapeseed, whale, tallow, lard, and other fixed oils As early as 1400 B.C., greases, made of a combination of calcium and fats, were used to lubricate chariot... vacuum tower The major properties that are controlled by vacuum distillation are viscosity, flash points, and carbon residue The viscosity of the oil base stock, the most important physical property for lubrication, is determined by the viscosity of the distillate Figure 2.13 illustrates vacuum distillation in terms of viscosity separation The heavy curve represents the distribution of viscosity in a . among the devices that require lubrication. The millions of automobiles, buses, airplanes, and trains depend on lubrication for operation, and it must be effective lubrication for dependability,. minimiza- tion of environmental impact. Many changes in the field of lubrication have occurred since the first edition of Lubrication Fundamentals was published more than 20 years ago. Today intricate. temperatures, smaller capacity lubricant reservoirs, and less frequent lubrication application up to and including fill-for- life lubrication. As a result, there has been an explosion in both higher