The impression is a mirror image of the top of the fish and indicates the fish's position in the hole, i.e., whether it is centered or off to one side. From this information, the correct fishing tool can be selected. A lead-filled cylindrical device used to ascertain the shape of a fish. 2. substances in acid-base that, in solution, change color or become colorless as the hydrogen ion concentration reaches a definite value, these values varying with the indicator. In other titrations, such as chloride, hardness, and other determinations, these substances change color at the end of the reaction.
Common indicators are phenolphthalein, and potassium chromate.
See acid fracture, acidize . It is added in small quantities to gasolines to prevent oxidation and gum formation, to lubricating oils to stop color change, and to corrosive environments to decrease corrosive action. It is reported in pounds per 100 square feet. See API-RP13B for details of test procedure. When moved from one location to another, the barge floats.