Thermal conductivity measurements on lead, tin, and zinc extending over the liquid as well as the solid states were reported by one of the authors in 1940. The present report extends this work to cover aluminum in both the liquid and solid phases. An improved technique is described. The lawk/&rgr;C=K(1/T) +K′ is found to hold for aluminum also, with the intercept,K′, the same for both states. The thermal conductivity (k) decreases with rise of temperature as it does for lead, tin, and zinc. On this point previous workers have published very conflicting data.