We report here an analysis that, for the first time, systematically normalizes the data from the HEAO 3 He~vy Nuclei Experiment on .the cosmic-ray abundances of all the elements heavier than germanium to that of .iron. In the range of atomic number Z, 33 ::;; Z ::;; 60, the analysis yields abundances of odd-even element pa1rs. These abundances are consistent with a cosmic-ray source having a composition similar to that of the solar system, but subject to so~rce. fractionation correlated with the first ionization potential (FIP) of each element. For Z > 60, the analysis yields abundances of element groups. For these heaviest nuclei, we find an enhancement of the abundance of the platinum group, elements with 74::;; Z::;; 80, relative to that in a propagated solar system source, and a corresponding increase in the abundance of the largely secondary elements in the range 62::;; Z ~ ?3. These abundances su~gest that there is an enhancement of the r-process contribution to the sour~ nucl:i m the:: Z > 60 charge region. Over the entire region of charge, standard leaky box models of propagation satisfactorily model secondary production.

New observations of galactic cosmic rays at higher energies (~ 400-780 MeV nucleon-1) than obtained in previous direct mass measurements have resulted in determinations of the isotopic composition of B, C, N, and 0. The derived cosmic-ray source abundances provide evidence for an enhancement of 18 0/ 6 0 by a factor of 5.6 ± 1.9 over the solar system value and give a 13 C/ 2 C ratio consistent with the solar system abundance ratio, but lower than some recent measurements of the local interstellar medium.