A new application of first kind levitation in magnetic fluids has been studied. Using the inertial properties of a diamagnetic or paramagnetic heavy body immersed in magnetic fluid positioned in a magnetic field gradient the possibility to achieve an inertial magnetofluidic sensor has been proved. A new method for detection and investigation of mechanical vibrations along the vertical direction was carried out. For verifying the method a device which receives mechanical vibrations and turns them into electrical signals has been made. The amplitude of electric signals and its dependence on the frequency and amplitude of mechanical vibrations has also been studied. >