The report summarizes results obtained since September, 1951, by total neutron yield experiments using 190 Mev deuterons and the MnSo4 tank method (UCRL-1375 and UCRL-1480). A new method of beam monitoring has resulted in establishing firmly the absolute yield for solid uranium and thorium primary targets backed by a solid uranium secondary. The beam monitoring was done by using a primary target built into a faraday cup. This method circumvents errors caused by recombination in the ionization chambers used previously.