贬别颈驳丑迟:听14听肠尘听
Width: 100 cm聽
顿别辫迟丑:听4听肠尘听
Materials: Wood, Brass, Leather聽
Manufacturer: Andrew H Baird聽聽
Date: c1900聽
Dr. Richard Fraser, Director of the Maude Abbott Medical聽Museum,聽provides a brief description of the function and/or use of the equipment.
This instrument (also known as an inductorium) has a graduated boxwood scale on a polished mahogany base that folds in two (when unfolded, it measures 1 meter in length). The inductorium was used to provide a variable amplitude periodic electrical stimulus to excite skeletal muscle or other excitable tissue (e.g., heart). On the base are two cylindrical coils. The primary coil (P) was firmly attached to the base and was connected through a power switch (PS) to an external direct current source of voltage, such as a battery. This switch periodically interrupted the current flowing into the primary from the battery. The periodic magnetic field produced by this periodic flow of current in the primary induced a periodic sequence of electrical pulses in the secondary coil (S), which were then taken by wires over to the biological preparation being stimulated (in the classic experiments of Galvani, the muscle in a frog鈥檚 leg). The amplitude of the stimulus could be increased (decreased) by sliding the moveable secondary coil closer to (further away from) the fixed primary coil.
