M. S.

Aluminum and magnesium wires were burned in 100% oxygen at pressures up to 550 psi. Two test series in moist atmospheres containing up to 25% water vapor were carried out with both metals at constant total pressure and at a constant temperature 0 of 280°F. In order to study these effects on the combustion reaction, the propagation rate of the burning zone along the wire was measured. It was believed that the participation of the condensed combustion products limited the reaction rate through their effect on the diffusion of oxygen. The products accumulation around the flame zone may also be responsible for the irregularities in the combustion velocity observed with both metals. The burning rate of aluminum and magnesium in moist atmospheres at higher pressures than atmospheric decreases with increasing moisture content. Aluminum wire combustion above 13-15% moisture did not occur. Fragmentation of the molten drop of metal ended the reaction. 120 Magnesium burned without fragmentation in atmospheres containing up to 25 per cent of water vapor. The reaction rate decreases continuously with increasing moisture concentration. / M. S.