(Received January 18, 1967)
Fine particles of Mg, Zn, Cd, Al, Fe, Cu and Ag were prepared by means of evaporation in helium gas. Compared with those prepared in argon gas (Japan. J. appl. Phys. 2 (1963) 702), the particle size was much smaller, provided the pressure was the same. To obtain the same size, the pressure of helium had to be about ten times as large as that of argon.