Amber is a fossil resin, supposed to be a product of the extinct Pinites Succinifer and other coniferous trees. Most of it is gathered on the shores of the Baltic between Koenigsberg and Memel. It is also found in small pieces at Gay Head, Mass., and in New Jersey green sand. It is found among the prehistoric remains of the Swiss Lake dwellers. When rubbed with a cloth it becomes excited with negative electricity. The Greek word for it is electron, which gave the name electricity to the modern science. Thales of Miletus, 600 B. C., and Theophrastus, about 300 B. C., both mention its electric properties or power of attracting small objects when rubbed. Ammeter. The commercial name for an ampere-meter, an instrument designed to show by direct reading the number of amperes of current which are passing through a circuit. A great variety of ammeters have been invented, based on different principles. The definitions following this one give some idea of the lines of construction followed. Synonym--Ampere meter.

Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects.