The history of the fight against friction in the development of machines is very long. For example, it can be found in a picture that describes the transportation of a gigantic stone statue left by ancient Egyptians [1]. The picture depicts people pouring some fluid from a jar before a sled on which a stone statue is mounted. It is surmised that this action was intended to reduce resistance by friction between the sled and the ground surface. It means that in those times, mankind already worked out a prudent method, such as "lubrication," in the fight against friction. In our day, people operate different machines by actively reducing friction by using methods of lubrication. Certainly, it goes without saying that lubricating oils play a very important role in this fight.
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