Temperature variations with respect to the specific gravity of glass fragments.

Professor Paul L. Kirk, Department of Biochemistry, University of California Medical School, Berkeley, is recognized as an authority on the identification of glass fragments and their physical properties. Several of his studies on the subject have appeared in this Journal. The comments which he makes on Prof. McCall's paper are based not only on his extensive work in this field but also upon special research on questions raised by this recent paper. In accord with its policy of full discussion of police science questions the Journal considers it fortunate to be able to publish a further discussion of this important problem. A. Melville Dollar is a graduate student in Criminology at the University of California who has carried out special research on the identification of glass fragments.-EDITOR.