A dentist’s instrument for hammering the fillings as inserted into teeth. It is a little hammer held in a suitable handle, and which is made to strike a rapid succession of blows by electro-magnetic motor mechanism.

The relative quantity of electricity residing as an electric charge upon a unit area of surface. It may be positive or negative. Synonyms–Density of Charge–Surface Density.

Removal of magnetism from a paramagnetic substance. It is principally used for watches which have become magnetized by exposure to the magnetic field surrounding dynamos or motors. The general principles of most methods are to rotate the object, as a watch, in a strong field, and while it is rotating to gradually remove it from [...]

A solution for batteries of the Bunsen and Grenet type. It is of the following composition: Water,                2,000 parts; potassium bichromate,   184 parts; sulphuric acid,         428 parts.

A small galvanic couple, immersed in a little floating cell and connected through a coil of wire immediately above them. When the exciting battery solution is placed in the cell the whole, as it floats in a larger vessel, turns until the coil lies at right angles to the magnetic needle. Sometimes the two plates [...]

Prefix originally used in the metric system to signify multiplying by ten, as dekameter, ten meters, dekagram, ten grams; now extended to many scientific terms.

The diminished sensibility to electro-therapeutic treatment exhibited by the human system with continuance of the treatment in question. The general lines of variation are stated in works on the subject.

The method of electrical measurements in which the deflection of the index of the measuring instrument is used as the measure of the current or other element under examination. It is the opposite of and is to be distinguished from the zero or null method, q. v. In the latter conditions are established which make [...]

In magnetism the movement out of the plane of the magnetic meridian of a magnetic needle, due to disturbance by or attraction towards a mass of iron or another magnet.

The field produced in a galvanometer by the current which is being tested, and which field deflects the needle, such deflection being the measure of the current strength.