Thanks to Project Zeno, Rome was recovering so well in fact that there were increasing population and resource pressures (including demand for slaves) to expand. The development of quinine from Cinchona bark back in 1837(1085) had greatly decreased fatalities from tropical diseases; allowing for deep penetrations into central Africa from long standing coastal outposts. However, especially in the case of the Congo: long supply trains, hazardous terrain, poor logistics, insufficient stocks of medicine, and native ambushes eventually put off the private entrepreneurs from conquering Africa's heart while making any offers of official attempts unpopular.