INTERSECTING M-BRANES AS 4-DIMENSIONAL BLACK-HOLES

We present two 1/8 supersymmetric intersecting p-brane solutions of 11 -dimensional supergravity which upon compactification to four dimensio ns reduce to extremal dyonic black holes with finite area of horizon. The first solution is a configuration of three intersecting 5-branes w ith an extra momentum flow along the common string. The second describ es a system of two 2-branes and two 5-branes. Related (by compactifica tion and T-duality) solution of type IIB theory corresponds to a compl etely symmetric configuration of four intersecting 3-branes. We sugges t methods for counting the BPS degeneracy of three intersecting 5-bran es which, in the macroscopic limit, reproduce the Bekenstein-Hawking e ntropy.