An instrument for measuring quantity of electricity in short current pulses. It is used in measuring magnetic quantities (flux, induction, field strength and others) and electrical quantities (large resistances, inductance, capacitance and others) whose values can be converted in the course of an experiment into a pulse of quantity of electricity proportional to them. The ballistic galvanometer is connected in series in the circuit through which the pulsed current flows. The instrument is a current integrator based on a moving-coil galvanometer in which the moment of inertia of the moving part has been increased artificially (the period of its free oscillations T0 >=15 s). If the duration of the current pulse is much less than T0 (less than 0.1 of it), the first and largest deflection after the current has passed (the ballistic throw a) is proportional to the quantity of electricity q that has passed through the coil of the ballistic galvanometer: q=ba. The sensitivity to the charge that has passed through the ballistic galvanometer — the ballistic sensitivity (and its reciprocal — the ballistic constant for charge b) — depends on the resistance of the external electric circuit to which the ballistic galvanometer is connected during the measurements. It is therefore calibrated at the same external resistance at which the measurements are to be made. The most sensitive modern ballistic galvanometers have a ballistic constant b~10-9 C*m/mm. The technical requirements for ballistic galvanometers are standardised in GOST 7324-80.