The present invention is a method for distinguishing, classifying and measuring soft and hard inclusions in a liquid metal that includes obtaining a flow through cell disposed on a tube with a top to allow the liquid metal to flow through the flow through cell and into the tube. There is also a mounting and a vacuum system disposed on top of the tube to draw the liquid metal through the flow through cell and into the tube that utilizes a pair of electrodes set inside and outside of the tube to apply an electric current to the liquid metal passing through the flow through cell. An electric resistance change is then measured and an electric resistance pulse is applied to the liquid metal to measure deformed behavior of the inclusions. The resistance pulse method can be used with liquid droplets, steel slag, bubbles and other deformable inclusions.