  Recently the Polish-American collaboration OGLE has reported the observation
of four possible microlensing events by monitoring, over several months, the
brightness of millions of stars in the region of the galactic bulge. If these
events are due to microlensing, the most accurate way to get information on the
mass of the dark compact objects, that acted as gravitational lenses, is to use
the method of the mass moments. Here I apply this method to the analysis of the
events detected by OGLE. The average mass turns out to be 0.28$M_{\odot}$,
suggesting that the lens objects are faint disk stars. The same method applied
to the five microlensing events detected so far by the EROS and MACHO
collaborations, which monitor stars in the Large Magellanic Cloud, leads to an
average value of 0.08$M_{\odot}$ for the dark compact halo objects.
